BibTeX and CFF

A potential crosswalk

Diego Hernangómez

Abstract

This article introduces a crosswalk between BibTeX and the Citation File Format (CFF) (Druskat et al. 2021), as implemented by the cffr package (Hernangómez 2021). The crosswalk aims to facilitate seamless translation between these two reference formats. Specifically, it proposes various crosswalk models tailored to different BibTeX entry types (Patashnik 1988). Additionally, the article includes practical examples using real BibTeX entries and offers tips for developers interested in implementing this crosswalk across various programming languages.

Disclaimer

This article was reviewed and updated in 2024, along with the release of cffr v1.0.0.

Citation

Please cite this article using this BibTeX entry:

@article{hernangomez2022,
    title        = {{BibTeX} and {CFF}, a potential crosswalk},
    author       = {Diego Hernangómez},
    year         = 2022,
    journal      = {The {cffr} package},
    volume       = {Vignettes},
    doi          = {10.21105/joss.03900},
    url          = {https://docs.ropensci.org/cffr/articles/bibtex_cff.html}
}

BibTeX and R

BibTeX is a well-known format for storing references created by Oren Patashnik and Leslie Lamport back in 1985. BibTeX can be reused by other software, such as LaTeX, to add references to scholarly works. An example structure of a BibTeX entry would be:

@book{einstein1921,
    title        = {Relativity: The Special and the General Theory},
    author       = {Einstein, A.},
    year         = 1920,
    publisher    = {Henry Holt and Company},
    address      = {London, United Kingdom},
    isbn         = 9781587340925
}

In this case, the entry (identified as einstein1921) refers to a book. This entry can then be used in a document to include references to it. In R (R Core Team 2021), we can replicate this structure using the bibentry() and toBibtex() functions:

entry <- bibentry("book",
  key = "einstein1921",
  title = "Relativity: The Special and the General Theory",
  author = person("A.", "Einstein"),
  year = 1920,
  publisher = "Henry Holt and Company",
  address = "London, United Kingdom",
  isbn = 9781587340925,
)

toBibtex(entry)
#> @Book{einstein1921,
#>   title = {Relativity: The Special and the General Theory},
#>   author = {A. Einstein},
#>   year = {1920},
#>   publisher = {Henry Holt and Company},
#>   address = {London, United Kingdom},
#>   isbn = {9781587340925},
#> }

The final results of the entry as a text string would be coerced as¹:

Einstein A (1920). Relativity: The Special and the General Theory. Henry Holt and Company, London, United Kingdom. ISBN 9781587340925.

Additionally, the cffr package (Hernangómez 2021) incorporates the following capabilities that can be used to read and transform BibTeX format into different formats:

• cff_read_bib() reads *.bib files.
• cff_read_bib_text() can read BibTeX entries that are already stored in a variable.
• A S3 method toBibtex.cff() that converts from cff objects to Bibtex objects (see utils::toBibtex()).

string <- "@book{einstein1921,
    title        = {Relativity: The Special and the General Theory},
    author       = {Einstein, A.},
    year         = 1920,
    publisher    = {Henry Holt and Company},
    address      = {London, United Kingdom},
    isbn         = 9781587340925}"

# To cff
library(cffr)
cff_format <- cff_read_bib_text(string)

cff_format
#> - type: book
#>   title: 'Relativity: The Special and the General Theory'
#>   authors:
#>   - family-names: Einstein
#>     given-names: A.
#>   year: '1920'
#>   publisher:
#>     name: Henry Holt and Company
#>     address: London, United Kingdom
#>   isbn: '9781587340925'

# To BibTeX with S3 method
toBibtex(cff_format)
#> @Book{einstein:1920,
#>   title = {Relativity: The Special and the General Theory},
#>   author = {A. Einstein},
#>   year = {1920},
#>   publisher = {Henry Holt and Company},
#>   address = {London, United Kingdom},
#>   isbn = {9781587340925},
#> }

BibTeX Definitions

Patashnik (1988) provides a comprehensive explanation of the BibTeX formats. Let’s distinguish between Entries and Fields.

Entries

Each entry type defines a different type of work. The 14 entry types defined in BibTeX are:

1. @article: An article from a journal or magazine.
2. @book: A book with an explicit publisher.
3. @booklet: A work that is printed and bound, but without a named publisher or sponsoring institution.
4. @conference: Equivalent to @inproceedings, included for Scribe compatibility.
5. @inbook: A part of a book, which may be a chapter (or section) and/or a range of pages.
6. @incollection: A part of a book having its own title.
7. @inproceedings: An article in conference proceedings.
8. @manual: Technical documentation.
9. @mastersthesis: A Master’s thesis.
10. @misc: Use this type when nothing else fits.
11. @phdthesis: A PhD thesis.
12. @proceedings: The proceedings of a conference.
13. @techreport: A report published by a school or other institution, usually numbered within a series.
14. @unpublished: A document having an author and title, but not formally published.

Other implementations similar to BibTeX, such as BibLaTeX (Kime, Wemheuer, and Lehman 2023), expand the definitions of entries to include other types such as online resources, software, or datasets. In BibTeX, these entries should be reclassified as @misc.

In R, the bibentry() base function does not implement @conference. However, we can use @inproceedings, instead given that the definition is identical.

Fields

Similar to the Entries, Patashnik (1988) also provides definitions for each of the possible standard BibTeX fields. While an entry must include certain required fields, it can also include additional fields that might be ignored in the raw implementation of BibTeX. Let’s explore some of these fields:

1. address: Typically represents the address of the publisher or another institution. In the case of @conference, @inproceedings and @proceedings this field indicates where the conference was held.
2. annote: An annotation. Although not used by standard bibliography styles, it may be relevant for producing annotated bibliographies.
3. author: Contains the name(s) of the author(s), following the format described in the LaTeX book (Lamport 1986).
4. booktitle: Refers to the title of a book, part of which is being cited. For @book entries, use the title field instead.
5. chapter: Indicates a chapter (or section) number.
6. crossref: Refers to the database key of the entry being cross-referenced.
7. edition: Specifies the edition of a @book, e.g., "Second". The ordinal should have the first letter capitalized; standard styles convert to lowercase when necessary.
8. editor: Contains the name(s) of editor(s), following the conventions in the LaTeX book (Lamport 1986). If there is also an author field, the editor field specifies the editor of the book or collection where the reference appears.
9. howpublished: Describes how something unusual has been published. The first word should be capitalized.
10. institution: Represents the sponsoring institution of a technical report.
11. journal: Refers to the name of a journal.
12. key: Used for alphabetizing, cross-referencing, and creating a label when author information is missing.
13. month: Indicates the month in which the work was published or, for an unpublished work, when it was written. Use the standard three-letter abbreviation (e.g., jan, feb, mar) as described in Appendix B.1.3 of the LaTeX book (Lamport 1986).
14. note: Provides any additional information that can assist the reader. The first word should be capitalized.
15. number: Represents the number of a journal, magazine, technical report, or a work in a series. An issue of a journal or magazine is usually identified by its volume and number. Organizations issuing technical reports often assign them numbers, and sometimes books are given numbers within a named series.
16. organization: Refers to the organization that sponsors a @conference or publishes a manual.
17. pages: Specifies one or more page numbers or a range of numbers (e.g., 42--111 or 7,41,73--97 or 43+).
18. publisher: Indicates the publisher’s name.
19. school: Provides the name of the school where a thesis was written.
20. series: Specifies the name of a series or set of books. When citing an entire book, the title field gives its title, and an optional series field provides the name of a series or multi-volume set in which the book is published.
21. title: Represents the work’s title.
22. type: Describes the type of a technical report (e.g., “Research Note”).
23. volume: Refers to the volume of a journal or multi-volume book.
24. year: Indicates the year of publication or, for an unpublished work, the year it was written. Generally, it should consist of four numerals (e.g., 1984).

As in the case of the Entries, other implementations such as BibLaTeX recognize additional fields.

In BibTeX, there exists a strict relationship between Entries and Fields. Depending on the type of entry, certain fields are required, while others are optional or even ignored.

The following table summarizes the relationship between Entries and Fields in BibTeX. Required fields are flagged as x, and optional fields are flagged as o. For more detailed information, refer to Patashnik (1988).

BibTeX, required fields by entry

field	@article	@book	@booklet	@inbook	@incollection	@conference, @inproceedings
address		o	o	o	o	o
annote
author	x	x	o	x	x	x
booktitle					x	x
chapter				x	o
crossref
edition		o		o	o
editor		x		x	o	o
howpublished			o
institution
journal	x
key
month	o	o	o	o	o	o
note	o	o	o	o	o	o
number	o	o		o	o	o
organization						o
pages	o			x	o	o
publisher		x		x	x	o
school
series		o		o	o	o
title	x	x	x	x	x	x
type				o	o
volume	o	o		o	o	o
year	x	x	o	x	x	x

(cont) BibTeX, required fields by entry

field	@manual	@mastersthesis, phdthesis	@misc	@proceedings	@techreport	@unpublished
address	o	o		o	o
annote
author	o	x	o		x	x
booktitle
chapter
crossref
edition	o
editor				o
howpublished			o
institution					x
journal
key
month	o	o	o	o	o	o
note	o	o	o	o	o	x
number				o	o
organization	o			o
pages
publisher				o
school		x
series				o
title	x	x	o	x	x	x
type		o			o
volume				o
year	o	x	o	x	x	o

It can be seen that only a subset of fields is necessary for any entry. For instance, title, year, and author are either required or optional in almost every entry, whereas crossref, annote, or key are never mandatory.

Citation File Format

Citation File Format (CFF) (Druskat et al. 2021) consists of plain text files containing both human- and machine-readable citation information for software and datasets. Within CFF, there are two important keys: preferred-citation and references, which play a crucial role in citing and referring to related works:

• preferred-citation: Refers to another work that should be cited instead of the software or dataset itself.
• references: Includes reference(s) to other creative works related to the software or dataset. Similar to a list of references in a scholarly paper, these references may encompass papers describing the abstract concepts of the software or algorithms implemented in the software version.

These two keys are expected to be definition.reference objects, as defined in the Guide to Citation File Format schema version 1.2.0, and they may contain the following keys:

Valid keys on CFF definition-reference objects

abbreviation	abstract	authors	collection-doi	collection-title
collection-type	commit	conference	contact	copyright
data-type	database-provider	database	date-accessed	date-downloaded
date-published	date-released	department	doi	edition
editors	editors-series	end	entry	filename
format	identifiers	institution	isbn	issn
issue	issue-date	issue-title	journal	keywords
languages	license	license-url	loc-end	loc-start
location	medium	month	nihmsid	notes
number	number-volumes	pages	patent-states	pmcid
publisher	recipients	repository	repository-artifact	repository-code
scope	section	senders	start	status
term	thesis-type	title	translators	type
url	version	volume	volume-title	year
year-original

These keys are equivalent to the BibTeX fields, with the exception of the key type. In CFF, this key defines the type of work², making it analogous to the BibTeX entries.

Proposed Crosswalk

The cffr package (Hernangómez 2021) provides utilities for converting BibTeX entries (via the R base function bibentry()) to CFF files and vice versa. This section describes how the conversion between both formats has been implemented. The crosswalk is partially based on Haines and The Ruby Citation File Format Developers (2021)³.

In the following two sections, I present an overview of the proposed mapping between the Entries and Fields of BibTeX and the CFF keys. After this initial mapping, I propose further transformations to enhance compatibility between both systems using different Entry Models.

For better clarity, when a field is in bold (e.g., @book, edition), it corresponds to BibTeX, and when the field is underlined (e.g., book, edition), it corresponds to CFF.

Entry/Type Crosswalk

For converting general BibTeX entries to CFF types, the following crosswalk is proposed:

Entry/Type crosswalk: From BibTeX to CFF

BibTeX Entry	CFF key: type	Notes
@article	article
@book, @inbook	book	@inbook is a book with chapter and/or pages
@booklet	pamphlet
@conference	conference-paper
@incollection	generic	Needs additional fields
@inproceedings	conference-paper
@manual	manual
@mastersthesis, @phdthesis	thesis	Identified by thesis-type
@misc	generic
@proceedings	proceedings
@techreport	report
@unpublished	unpublished

The previous crosswalk has the following specifications:

• @book, @inbook, and @incollection are closely related in BibTeX⁴. While @inbook and @incollection both reference parts of a @book, the former is used for citing sections, chapters, pages, or other specific parts, whereas the latter is used for citing parts with a specific title. Since CFF allows keys type:book and collection-type: book, we may utilize a combination of these fields to tag each entry type in CFF accordingly.
• @mastersthesis and @phdthesis would be tagged using a combination of type:thesis and thesis-type.

Additionally, considering that CFF allows for a wide range of values⁵ for the type field, the following conversion would be applied from CFF to BibTeX:

Entry/Type crosswalk: From CFF to BibTeX

CFF key: type	BibTeX Entry	Notes
book	@book, @inbook	@inbook is a book with section or start/end (reference to page number or range).
conference, conference-paper	@inproceedings
article, magazine-article, newspaper-article	@article
manual	@manual
pamphlet	@booklet
proceedings	@proceedings
report	@techreport
thesis	@mastersthesis, @phdthesis	Using thesis-type
unpublished	@unpublished
generic	@misc, @incollection	@incollection is a generic with year,publisher,collection-title
<any other value>	@misc

Fields/Key Crosswalk

There is a significant similarity between the definitions and names of certain BibTeX fields and CFF keys. While the equivalence is straightforward in some cases, there are instances where certain keys need to be processed depending on the entry type.

BibTeX - CFF Field/Key crosswalk

BibTeX Field	CFF key	Notes
address	Several possibilities	In BibTeX it may be the address of a publisher, conference, organization, institution or school.
annote	Not clear, won’t be mapped
author	authors
booktitle	collection-title
chapter	section
crossref	Not clear, won’t be mapped
edition	edition
editor	editors
howpublished	medium
institution, school, organization	institution	No overlapping on BibteX requirements
journal	journal
key	Not clear, won’t be mapped
month	month	Fallback: information in date-published
note	notes
number	issue
pages	start & end
publisher	publisher
series	collection-title if no booktitle
title	title
type	Won’t be mapped	This is a special key in CFF resembling the BibteX entry.
volume	volume
year	year	Fallback: information in date-published

We provide more detail on some of the mappings presented in the table above:

• Some fields are not mapped because there is no clear equivalence with CFF keys (such as annote, crossref, and key). Regarding the type field, the CFF key type corresponds to the identifier of the work (similar to an entry in BibTeX), therefore, BibTeX type won’t be mapped. These fields are always optional in BibTeX.

• For the address field, its intended use in BibTeX varies depending on the entry type (e.g., for @inproceedings, it denotes the address of the conference, while for @mastersthesis/@phdthesis, is the address of the school, etc.). Mapping between BibTeX and CFF becomes more complex when related to institutions, resulting in varying final mappings in CFF. When converting from CFF to BibTeX, we propose to follow the same entry-based logic, using the key location as a fallback value when converting to address.

• In relation with this complexity mentioned above, institution, organization and school would be mapped to institution.

• series would be mapped to collection-title only on those entries that does not requires booktitle. In practice, this means that collection-title would correspond to booktitle for incollection and inproceedings, and in the rest of cases it would correspond to series. A consequence of this is that series information would be lost for incollection and inproceedings, but on those cases is an optional field.

• When converting from CFF to BibTeX, we propose to use date-published as a fallback for extracting month and year fields.

• When pages is provided as a range separated by --, i.e, pages = {3–5} would be coerced as start: 3, end: 5 in CFF.

BibLaTeX

Additionally, there are other CFF keys that correspond to BibLaTeX fields. We propose to include these fields in the crosswalk⁶, even though they are not part of the core BibTeX fields definition.

BibLaTeX - CFF Field/Key crosswalk

BibLaTeX Field	CFF key
abstract	abstract
date	date-published
doi	doi
file	filename
isbn	isbn
issn	issn
issuetitle	issue-title
keywords	keywords
pagetotal	pages
translator	translators
url	url
urldate	date-accessed
version	version

Entry Models

This section presents the specific mapping proposed for each of the BibTeX entries, providing further information on how each field is treated. Examples are adapted from the xampl.bib file provided with the bibtex package (Patashnik and Berry 2010).

@article

The crosswalk of @article does not require any special treatment.

@article Model

BibTeX	CFF	Notes
@article	type: article, magazine-article, newspaper-article
author (required)	authors
title (required)	title
journal (required)	journal
year (required)	year
volume	volume
number	issue
pages	start and end
month	month
note	notes

Examples

BibTeX entry

@article{article-full,
    title        = {The Gnats and Gnus Document Preparation System},
    author       = {Leslie A. Aamport},
    year         = 1986,
    month        = jul,
    journal      = {{G-Animal's} Journal},
    volume       = 41,
    number       = 7,
    pages        = {73+},
    note         = {This is a full ARTICLE entry}
}

CFF entry

- type: article
  title: The Gnats and Gnus Document Preparation System
  authors:
  - family-names: Aamport
    given-names: Leslie A.
  year: '1986'
  month: '7'
  journal: G-Animal's Journal
  volume: '41'
  issue: '7'
  notes: This is a full ARTICLE entry
  start: 73+

From CFF to BibTeX

@Article{aamport:1986,
  title = {The Gnats and Gnus Document Preparation System},
  author = {Leslie A. Aamport},
  year = {1986},
  month = {jul},
  journal = {G-Animal's Journal},
  volume = {41},
  number = {7},
  pages = {73+},
  note = {This is a full ARTICLE entry},
}

@book / @inbook

In terms of the fields required in BibTeX, the primary difference between @book and @inbook is that @inbook requires a chapter or page field, while @book does not even allow these fields as optional. Therefore, we propose that an @inbook entry in CFF be treated as a @book with the following supplementary fields:

1. section: To denote the specific chapter within the book.
2. start-end: To indicate the range of pages covered by the section.

Additionally, note that in CFF, the series field corresponds to collection-title, and the address field represents the publisher’s address. By last, the key collection-type would be populated with book-series.

@book / @inbook Model

BibTeX	CFF	Notes
@book, @inbook	type: book	If section or start-end informed, it would be treated as @inbook
author (required)	authors	At least one of author,editor required
editor (required)	editors	At least one of author,editor required
title (required)	title
publisher (required)	publisher
year (required)	year
chapter (required in @inbook only)	section	Not even optional in @book
pages (required in @inbook only)	start and end	Not even optional in @book
volume	volume
number	issue
series	collection-title
address	address property of publisher
edition	edition
month	month
note	notes
type	Ignored	Only optional in @inbook

There are notable differences in how BibTeX and BibLaTeX handle the @inbook entry (further discussed in the Appendix A). We propose to treat a BibLaTeX @inbook as a BibTeX @incollection.

Examples: @book

BibTeX entry

@book{book-full,
    title        = {Seminumerical Algorithms},
    author       = {Donald E. Knuth},
    year         = 1981,
    month        = 10,
    publisher    = {Addison-Wesley},
    address      = {Reading, Massachusetts},
    series       = {The Art of Computer Programming},
    volume       = 2,
    note         = {This is a full BOOK entry},
    edition      = {Second}
}

CFF entry

- type: book
  title: Seminumerical Algorithms
  authors:
  - family-names: Knuth
    given-names: Donald E.
  year: '1981'
  month: '10'
  publisher:
    name: Addison-Wesley
    address: Reading, Massachusetts
  collection-title: The Art of Computer Programming
  collection-type: book
  volume: '2'
  notes: This is a full BOOK entry
  edition: Second

From CFF to BibTeX

@Book{knuth:1981,
  title = {Seminumerical Algorithms},
  author = {Donald E. Knuth},
  year = {1981},
  month = {oct},
  publisher = {Addison-Wesley},
  address = {Reading, Massachusetts},
  series = {The Art of Computer Programming},
  volume = {2},
  note = {This is a full BOOK entry},
  edition = {Second},
}

Examples: @inbook

BibTeX entry

@inbook{inbook-full,
    title        = {Fundamental Algorithms},
    author       = {Donald E. Knuth},
    year         = 1973,
    month        = 10,
    publisher    = {Addison-Wesley},
    address      = {Reading, Massachusetts},
    series       = {The Art of Computer Programming},
    volume       = 1,
    pages        = {10--119},
    note         = {This is a full INBOOK entry},
    edition      = {Second},
    type         = {Section},
    chapter      = {1.2}
}

CFF entry

- type: book
  title: Fundamental Algorithms
  authors:
  - family-names: Knuth
    given-names: Donald E.
  year: '1973'
  month: '10'
  publisher:
    name: Addison-Wesley
    address: Reading, Massachusetts
  collection-title: The Art of Computer Programming
  collection-type: book
  volume: '1'
  notes: This is a full INBOOK entry
  edition: Second
  section: '1.2'
  start: '10'
  end: '119'

From CFF to BibTeX

@InBook{knuth:1973,
  title = {Fundamental Algorithms},
  author = {Donald E. Knuth},
  year = {1973},
  month = {oct},
  publisher = {Addison-Wesley},
  address = {Reading, Massachusetts},
  series = {The Art of Computer Programming},
  volume = {1},
  pages = {10--119},
  note = {This is a full INBOOK entry},
  chapter = {1.2},
  edition = {Second},
}

@booklet

In @booklet address is mapped to location.

@booklet Model

BibTeX	CFF	Notes
@booklet	type: pamphlet
title (required)	title
author	authors
howpublished	medium
address	location
month	month
year	year
note	notes

Examples

BibTeX entry

@booklet{booklet-full,
    title        = {The Programming of Computer Art},
    author       = {Jill C. Knvth},
    date         = {1988-03-14},
    month        = feb,
    address      = {Stanford, California},
    note         = {This is a full BOOKLET entry},
    howpublished = {Vernier Art Center}
}

CFF entry

- type: pamphlet
  title: The Programming of Computer Art
  authors:
  - family-names: Knvth
    given-names: Jill C.
  date-published: '1988-03-14'
  month: '2'
  location:
    name: Stanford, California
  notes: This is a full BOOKLET entry
  medium: Vernier Art Center
  year: '1988'

From CFF to BibTeX

@Booklet{knvth:1988,
  title = {The Programming of Computer Art},
  author = {Jill C. Knvth},
  year = {1988},
  month = {feb},
  address = {Stanford, California},
  note = {This is a full BOOKLET entry},
  howpublished = {Vernier Art Center},
  date = {1988-03-14},
}

@conference / @inproceedings

Note that in this case, organization is mapped to institution. Additionally, series would be ignored as there is not clear mapping on CFF for this field.

@conference / @inproceedings Model

BibTeX	CFF	Notes
@conference / @inproceedings	type: conference-paper, conference
author (required)	authors
title (required)	title
booktitle (required)	collection-title and conference	Additionally collection-type would be populated as “proceedings”
year (required)	year
editor	editors
volume	volume
number	issue
series	Ignored
pages	start and end
address	address property of conference
month	month
organization	institution
publisher	publisher
note	notes

Examples

BibTeX entry

@inproceedings{inproceedings-full,
    title        = {On Notions of Information Transfer in {VLSI} Circuits},
    author       = {Alfred V. Oaho and Jeffrey D. Ullman and Mihalis Yannakakis},
    year         = 1983,
    month        = mar,
    booktitle    = {Proc. Fifteenth Annual ACM Symposium on the Theory of Computing},
    publisher    = {Academic Press},
    address      = {Boston},
    series       = {All ACM Conferences},
    number       = 17,
    pages        = {133--139},
    editor       = {Wizard V. Oz and Mihalis Yannakakis},
    organization = {The OX Association for Computing Machinery}
}

CFF entry

- type: conference-paper
  title: On Notions of Information Transfer in VLSI Circuits
  authors:
  - family-names: Oaho
    given-names: Alfred V.
  - family-names: Ullman
    given-names: Jeffrey D.
  - family-names: Yannakakis
    given-names: Mihalis
  year: '1983'
  month: '3'
  collection-title: Proc. Fifteenth Annual ACM Symposium on the Theory of Computing
  collection-type: proceedings
  publisher:
    name: Academic Press
  issue: '17'
  editors:
  - family-names: Oz
    given-names: Wizard V.
  - family-names: Yannakakis
    given-names: Mihalis
  institution:
    name: The OX Association for Computing Machinery
  start: '133'
  end: '139'
  conference:
    name: Proc. Fifteenth Annual ACM Symposium on the Theory of Computing
    address: Boston

From CFF to BibTeX

@InProceedings{oaho_etall:1983,
  title = {On Notions of Information Transfer in VLSI Circuits},
  author = {Alfred V. Oaho and Jeffrey D. Ullman and Mihalis Yannakakis},
  year = {1983},
  month = {mar},
  booktitle = {Proc. Fifteenth Annual ACM Symposium on the Theory of Computing},
  publisher = {Academic Press},
  address = {Boston},
  editor = {Wizard V. Oz and Mihalis Yannakakis},
  number = {17},
  pages = {133--139},
  organization = {The OX Association for Computing Machinery},
}

@incollection

As booktitle is a required field, we propose to map that field to collection-title and the type to generic. Therefore, an @incollection is a type: generic with a collection-title key.

Additionally, series and type would be ignored as there is not clear mapping on CFF for this field.

@incollection Model

BibTeX	CFF	Notes
@incollection	type: generic	Including a collection-title value
author (required)	authors
title (required)	title
booktitle (required)	collection-title	Additionally collection-type would be populated as “collection”
publisher (required)	publisher
year (required)	year
editor	editors
volume	volume
number	issue
series	Ignored
type	Ignored
chapter	section
pages	start and end
address	address property of publisher
edition	edition
month	month
note	notes

Examples

BibTeX entry

@incollection{incollection-full,
    title        = {Semigroups of Recurrences},
    author       = {Daniel D. Lincoll},
    year         = 1977,
    month        = sep,
    booktitle    = {High Speed Computer and Algorithm Organization},
    publisher    = {Academic Press},
    address      = {New York},
    series       = {Fast Computers},
    number       = 23,
    pages        = {179--183},
    note         = {This is a full INCOLLECTION entry},
    editor       = {David J. Lipcoll and D. H. Lawrie and A. H. Sameh},
    chapter      = 3,
    type         = {Part},
    edition      = {Third}
}

CFF entry

- type: generic
  title: Semigroups of Recurrences
  authors:
  - family-names: Lincoll
    given-names: Daniel D.
  year: '1977'
  month: '9'
  collection-title: High Speed Computer and Algorithm Organization
  collection-type: collection
  publisher:
    name: Academic Press
    address: New York
  issue: '23'
  notes: This is a full INCOLLECTION entry
  editors:
  - family-names: Lipcoll
    given-names: David J.
  - family-names: Lawrie
    given-names: D. H.
  - family-names: Sameh
    given-names: A. H.
  section: '3'
  edition: Third
  start: '179'
  end: '183'

From CFF to BibTeX

@InCollection{lincoll:1977,
  title = {Semigroups of Recurrences},
  author = {Daniel D. Lincoll},
  year = {1977},
  month = {sep},
  booktitle = {High Speed Computer and Algorithm Organization},
  publisher = {Academic Press},
  address = {New York},
  editor = {David J. Lipcoll and D. H. Lawrie and A. H. Sameh},
  number = {23},
  pages = {179--183},
  note = {This is a full INCOLLECTION entry},
  chapter = {3},
  edition = {Third},
}

@manual

As in the case of @conference / @inproceedings, organization is mapped to institution.

@manual Model

BibTeX	CFF	Notes
@manual	type: manual
title (required)	title
author	authors
organization	institution
address	address property of organization	On missing organization mapped to location
edition	edition
month	month
year	year
note	notes

Examples

BibTeX entry

Note that month can’t be coerce to a single integer in the range 1--12 as required on CFF, so it is ignored to avoid validation errors.

@manual{manual-full,
  title        = {The Definitive Computer Manual},
    author       = {Larry Manmaker},
    year         = 1986,
    month        = {apr-may},
    address      = {Silicon Valley},
    note         = {This is a full MANUAL entry},
    organization = {Chips-R-Us},
    edition      = {Silver}
}

CFF entry

- type: manual
  title: The Definitive Computer Manual
  authors:
  - family-names: Manmaker
    given-names: Larry
  year: '1986'
  month: '4'
  notes: This is a full MANUAL entry
  institution:
    name: Chips-R-Us
    address: Silicon Valley
  edition: Silver

From CFF to BibTeX

@Manual{manmaker:1986,
  title = {The Definitive Computer Manual},
  author = {Larry Manmaker},
  year = {1986},
  month = {apr},
  address = {Silicon Valley},
  note = {This is a full MANUAL entry},
  edition = {Silver},
  organization = {Chips-R-Us},
}

@mastersthesis / @phdthesis

In terms of field required on BibTeX, it is identical for both @mastersthesis and @phdthesis.

We propose here to identify each type of thesis using the key thesis-type So if thesis-type contains a regex pattern (?i)(phd) it would be recognized as @phdthesis.

Additionally, school would be mapped to institution.

@mastersthesis / @phdthesis Model

BibTeX	CFF	Notes
@mastersthesis, @phdthesis	type: thesis	Use also thesis-type for identifying the thesis type.
author (required)	authors
title (required)	title
school (required)	institution
year (required)	year
type	Ignored
address	address property of institution
month	month
note	notes

Examples: @mastersthesis

BibTeX entry

@mastersthesis{mastersthesis-full,
    title        = {Mastering Thesis Writing},
    author       = {Edouard Masterly},
    year         = 1988,
    month        = jun,
    address      = {English Department},
    note         = {This is a full MASTERSTHESIS entry},
    school       = {Stanford University},
    type         = {Master's project}
}

CFF entry

- type: thesis
  title: Mastering Thesis Writing
  authors:
  - family-names: Masterly
    given-names: Edouard
  year: '1988'
  month: '6'
  notes: This is a full MASTERSTHESIS entry
  institution:
    name: Stanford University
    address: English Department
  thesis-type: Master's Thesis

From CFF to BibTeX

@MastersThesis{masterly:1988,
  title = {Mastering Thesis Writing},
  author = {Edouard Masterly},
  year = {1988},
  month = {jun},
  address = {English Department},
  note = {This is a full MASTERSTHESIS entry},
  school = {Stanford University},
}

Examples: @phdthesis

BibTeX entry

@phdthesis{phdthesis-full,
    title        = {Fighting Fire with Fire: Festooning {F}rench Phrases},
    author       = {F. Phidias Phony-Baloney},
    year         = 1988,
    month        = jun,
    address      = {Department of French},
    note         = {This is a full PHDTHESIS entry},
    school       = {Fanstord University},
    type         = {{PhD} Dissertation}
}

CFF entry

- type: thesis
  title: 'Fighting Fire with Fire: Festooning French Phrases'
  authors:
  - family-names: Phony-Baloney
    given-names: F. Phidias
  year: '1988'
  month: '6'
  notes: This is a full PHDTHESIS entry
  institution:
    name: Fanstord University
    address: Department of French
  thesis-type: PhD Thesis

From CFF to BibTeX

@PhdThesis{phonybaloney:1988,
  title = {Fighting Fire with Fire: Festooning French Phrases},
  author = {F. Phidias Phony-Baloney},
  year = {1988},
  month = {jun},
  address = {Department of French},
  note = {This is a full PHDTHESIS entry},
  school = {Fanstord University},
}

@misc

The crosswalk of @misc does not require any special treatment. This entry does not require any field.

Note also that it is mapped to type: generic as @incollection, but in this case booktitle is not even an option, so the proposed definition should cover both @misc and @incollection without problems.

@misc Model

BibTeX	CFF	Notes
@misc	type: generic
author	authors
title	title
howpublished	medium
month	month
year	year
note	notes

Examples

BibTeX entry

@misc{misc-full,
    title        = {Handing out random pamphlets in airports},
    author       = {Joe-Bob Missilany},
    year         = 1984,
    month        = oct,
    note         = {This is a full MISC entry},
    howpublished = {Handed out at O'Hare}
}

CFF entry

- type: generic
  title: Handing out random pamphlets in airports
  authors:
  - family-names: Missilany
    given-names: Joe-Bob
  year: '1984'
  month: '10'
  notes: This is a full MISC entry
  medium: Handed out at O'Hare

From CFF to BibTeX

@Misc{missilany:1984,
  title = {Handing out random pamphlets in airports},
  author = {Joe-Bob Missilany},
  year = {1984},
  month = {oct},
  note = {This is a full MISC entry},
  howpublished = {Handed out at O'Hare},
}

@proceedings

The proposed model is consistent with @conference / @inproceedings. Note that @proceedings does not prescribe a author field. On this cases, as authors is required on CFF, we would use anonymous⁷ when converting to CFF and omit it on the conversion from CFF to BibTeX.

@proceedings Model

BibTeX	CFF	Notes
@proceedings	type: proceedings
title (required)	title and conference
year (required)	year
editor	editors
volume	volume
number	issue
series	collection-title	Additionally collection-type would be populated as “proceedings”
address	address property of conference
month	month
organization	institution
publisher	publisher
note	notes

Examples

BibTeX entry

@proceedings{proceedings-full,
    title        = {Proc. Fifteenth Annual ACM Symposium on the Theory of Computing},
    year         = 1983,
    month        = mar,
    publisher    = {Academic Press},
    address      = {Boston},
    series       = {All ACM Conferences},
    number       = 17,
    note         = {This is a full PROCEEDINGS entry},
    editor       = {Wizard V. Oz and Mihalis Yannakakis},
    organization = {The OX Association for Computing Machinery}
}

CFF entry

- type: proceedings
  title: Proc. Fifteenth Annual ACM Symposium on the Theory of Computing
  authors:
  - name: anonymous
  year: '1983'
  month: '3'
  publisher:
    name: Academic Press
  collection-title: All ACM Conferences
  collection-type: proceedings
  issue: '17'
  notes: This is a full PROCEEDINGS entry
  editors:
  - family-names: Oz
    given-names: Wizard V.
  - family-names: Yannakakis
    given-names: Mihalis
  institution:
    name: The OX Association for Computing Machinery
  conference:
    name: All ACM Conferences
    address: Boston

From CFF to BibTeX

@Proceedings{oz_etall:1983,
  title = {Proc. Fifteenth Annual ACM Symposium on the Theory of Computing},
  year = {1983},
  month = {mar},
  publisher = {Academic Press},
  address = {Boston},
  editor = {Wizard V. Oz and Mihalis Yannakakis},
  series = {All ACM Conferences},
  number = {17},
  note = {This is a full PROCEEDINGS entry},
  organization = {The OX Association for Computing Machinery},
}

@techreport

The crosswalk of @techreport does not require any special treatment.

@techreport Model

BibTeX	CFF	Notes
@techreport	type: report
author (required)	authors
title (required)	title
institution (required)	institution
year (required)	year
type	Ignored
number	issue
address	address property of institution
month	month
note	notes

Examples

BibTeX entry

@techreport{techreport-full,
    title        = {A Sorting Algorithm},
    author       = {Tom Terrific},
    year         = 1988,
    month        = oct,
    address      = {Computer Science Department, Fanstord, California},
    number       = 7,
    note         = {This is a full TECHREPORT entry},
    institution  = {Fanstord University},
    type         = {Wishful Research Result}
}

CFF entry

- type: report
  title: A Sorting Algorithm
  authors:
  - family-names: Terrific
    given-names: Tom
  year: '1988'
  month: '10'
  issue: '7'
  notes: This is a full TECHREPORT entry
  institution:
    name: Fanstord University
    address: Computer Science Department, Fanstord, California

From CFF to BibTeX

@TechReport{terrific:1988,
  title = {A Sorting Algorithm},
  author = {Tom Terrific},
  year = {1988},
  month = {oct},
  address = {Computer Science Department, Fanstord, California},
  number = {7},
  note = {This is a full TECHREPORT entry},
  institution = {Fanstord University},
}

@unpublished

The crosswalk of @unpublished does not require any special treatment.

@unpublished Model

BibTeX	CFF	Notes
@unpublished	type: unpublished
author (required)	authors
title (required)	title
note (required)	notes
month	month
year	year

Examples

BibTeX entry

@unpublished{unpublished-minimal,
    title        = {Lower Bounds for Wishful Research Results},
    author       = {Ulrich Underwood and Ned Net and Paul Pot},
    note         = {Talk at Fanstord University (this is a minimal UNPUBLISHED entry)}
}

CFF entry

- type: unpublished
  title: Lower Bounds for Wishful Research Results
  authors:
  - family-names: Underwood
    given-names: Ulrich
  - family-names: Net
    given-names: Ned
  - family-names: Pot
    given-names: Paul
  notes: Talk at Fanstord University (this is a minimal UNPUBLISHED entry)

From CFF to BibTeX

@Unpublished{underwood_etall,
  title = {Lower Bounds for Wishful Research Results},
  author = {Ulrich Underwood and Ned Net and Paul Pot},
  note = {Talk at Fanstord University (this is a minimal UNPUBLISHED entry)},
}

Appendix A: @inbook in BibTeX and BibLaTeX

The definition of @inbook and @incollection in BibTeX (Patashnik 1988) is as follows:

• @inbook: A part of a book, which may be a chapter (or section) and/or a range of pages. Required fields: author or editor, title, chapter and/or pages, publisher, year (…)

• @incollection: A part of a book having its own title. Required fields: author, title, booktitle, publisher, year (…)

Whereas BibLaTeX (Kime, Wemheuer, and Lehman 2023) specifies:

• @inbook: A part of a book which forms a self-contained unit with its own title. Note that the profile of this entry type is different from standard BibTeX, see § 2.3.1. Required fields: author, title, booktitle, year/date (…).

When considering required fields, an important difference is booktitle requirement in BibLaTeX. Notably, BibTeX @incollection requires also this field. Moreover, both BibTeX @incollection and BibLaTeX @inbook emphasize its reference to “a part of a book (…) with its own title”.

In this document, the proposed crosswalk ensures full compatibility with BibTeX. Hence, we propose to consider a BibLaTeX @inbook entry as equivalent to a BibTeX @incollection, given the congruence in their definitions and field requirements.

Examples

BibTeX entry

@inbook{inbook-biblatex,
    author       = {Yihui Xie and Christophe Dervieux and Emily Riederer},
    title        = {Bibliographies and citations},
    booktitle    = {{R} Markdown Cookbook},
    date         = {2023-12-30},
    publisher    = {Chapman and Hall/CRC},
    address      = {Boca Raton, Florida},
    series       = {The {R} Series},
    isbn         = 9780367563837,
    url          = {https://bookdown.org/yihui/rmarkdown-cookbook},
    chapter      = {4.5}
}

CFF entry

- type: generic
  title: Bibliographies and citations
  authors:
  - family-names: Xie
    given-names: Yihui
  - family-names: Dervieux
    given-names: Christophe
  - family-names: Riederer
    given-names: Emily
  collection-title: R Markdown Cookbook
  collection-type: collection
  date-published: '2023-12-30'
  publisher:
    name: Chapman and Hall/CRC
    address: Boca Raton, Florida
  isbn: '9780367563837'
  url: https://bookdown.org/yihui/rmarkdown-cookbook
  section: '4.5'
  year: '2023'
  month: '12'

From CFF to BibTeX

@InCollection{xie_etall:2023,
  title = {Bibliographies and citations},
  author = {Yihui Xie and Christophe Dervieux and Emily Riederer},
  year = {2023},
  month = {dec},
  booktitle = {R Markdown Cookbook},
  publisher = {Chapman and Hall/CRC},
  address = {Boca Raton, Florida},
  isbn = {9780367563837},
  url = {https://bookdown.org/yihui/rmarkdown-cookbook},
  chapter = {4.5},
  date = {2023-12-30},
}

Appendix B: CFF key:type values

From Druskat et al. (2019) Table 4: Complete list of CFF reference types.

Complete list of CFF reference types.

Reference type string	Description
art	A work of art, e.g., a painting
article
audiovisual
bill	A legal bill
blog	A blog post
book	A book or e-book
catalogue
conference
conference-paper
data	A data set
database	An aggregated or online database
dictionary
edited-work	An edited work, e.g., a book
encyclopedia
film-broadcast	A film or broadcast
generic	The fallback type
government-document
grant	A research or other grant
hearing
historical-work	A historical work, e.g., a medieval manuscript
legal-case
legal-rule
magazine-article
manual	A manual
map	A geographical map
multimedia	A multimedia file
music	A music file or sheet music
newspaper-article
pamphlet
patent
personal-communication
proceedings	Conference proceedings
report
serial
slides	Slides, i.e., a published slide deck
software	Software
software-code	Software source code
software-container	A software container (e.g., a docker container)
software-executable	An executable software, i.e., a binary/artifact
software-virtual-machine	A virtual machine/vm image
sound-recording
standard
statute
thesis	An academic thesis
unpublished
video	A video recording
website

References

Druskat, Stephan, Jurriaan H. Spaaks, Neil Chue Hong, Robert Haines, and James Baker. 2019. “Citation File Format (CFF) - Specifications.” https://doi.org/10.5281/ZENODO.3515946.

Druskat, Stephan, Jurriaan H. Spaaks, Neil Chue Hong, Robert Haines, James Baker, Spencer Bliven, Egon Willighagen, David Pérez-Suárez, and Alexander Konovalov. 2021. “Citation File Format.” https://doi.org/10.5281/zenodo.5171937.

Haines, Robert, and The Ruby Citation File Format Developers. 2021. “Ruby CFF Library.” Zenodo. https://doi.org/10.5281/ZENODO.1184077.

Hernangómez, Diego. 2021. “cffr: Generate Citation File Format Metadata for R Packages.” Journal of Open Source Software 6 (67): 3900. https://doi.org/10.21105/joss.03900.

Kime, Philip, Moritz Wemheuer, and Philipp Lehman. 2023. “The biblatex Package.” https://osl.ugr.es/CTAN/macros/latex/contrib/biblatex/doc/biblatex.pdf.

Lamport, Leslie. 1986. LaTeX: A Document Preparation System. Reading, Mass: Addison-Wesley Pub. Co.

Patashnik, Oren. 1988. “BIBTEXTING.” https://osl.ugr.es/CTAN/biblio/bibtex/base/btxdoc.pdf.

Patashnik, Oren, and Karl Berry. 2010. “CTAN: Package Bibtex.” https://ctan.org/pkg/bibtex.

R Core Team. 2021. R: A Language and Environment for Statistical Computing. Vienna, Austria: R Foundation for Statistical Computing; R Foundation for Statistical Computing. https://www.R-project.org/.

Rees, Clea F. 2017. “BibLaTeX Cheat Sheet.” https://osl.ugr.es/CTAN/info/biblatex-cheatsheet/biblatex-cheatsheet.pdf.

Xie, Yihui, Christophe Dervieux, and Emily Riederer. 2020. “Bibliographies and Citations.” In R Markdown Cookbook. The R Series. Boca Raton, Florida: Chapman; Hall/CRC. https://bookdown.org/yihui/rmarkdown-cookbook.