These functions are gone, no longer available.
Details
cr_citation(): Crossref is trying to sunset their OpenURL API, which this function uses. So this function is now removed. See the functioncr_cn(), which does the same things, but with more functionality, using the new Crossref API.pmid2doi()anddoi2pmid(): The API behind these functions is down for good, seeid_converter()for similar functionality.cr_search(): The functionality of this function can be achieved with the new Crossref API. See functionscr_works()et al.cr_search_free(): The functionality of this function can be achieved with the new Crossref API. See functionscr_works()et al.crosscite(): The functionality of this function can be achieved withcr_cn()cr_fundref(): Crossref changed their name "fundref" to "funders", so we've changed our function, seecr_funders()cr_ft_text(): This function and other text mining functions are incorporated in a new packagecrminer.cr_ft_links(): This function and other text mining functions are incorporated in a new packagecrminer.cr_ft_pdf(): This function and other text mining functions are incorporated in a new packagecrminer.cr_ft_plain(): This function and other text mining functions are incorporated in a new packagecrminer.cr_ft_text(): This function and other text mining functions are incorporated in a new packagecrminer.cr_ft_xml(): This function and other text mining functions are incorporated in a new packagecrminer.as.tdmurl(): This function and other text mining functions are incorporated in a new packagecrminer.extract_xpdf(): This function and other text mining functions are incorporated in a new packagecrminer.
