Create a citation string from package specific BibTex entries, suitable to be used in Rd files. The entries are looked in a file named REFERNCES.bib in the package's root directory (i.e. inst/ in development mode).
packageReference(key, short = FALSE, PACKAGE = NULL)
a character string containing the text formated BibTex entries
character vector of BibTex keys
logical that indicates if the reference should be shorten as First Author et al. if it has more than one author.
package in which the BiBTeX entry is defined.