I have a problem almost identically to this old other question. The differences are that I am using Zotero and the IEEEtran bib style.
Zotero basically does the same thing as Mendeley, i.e. producing language fields in the .bib with the value en etc. So this difference is insignificant to this question and I state it here only for search engine users.
The IEEEtran bib style emits some code that apparently checks if the language's value is a defined babel language. If that's not the case it produces a warning:
** WARNING: IEEEtran.bst: No hyphenation pattern has been
** loaded for the language `en'. Using the pattern for
This comes from the following code:
\providecommand{\BIBforeignlanguage}[2]{{%
\expandafter\ifx\csname l@#1\endcsname\relax
\typeout{** WARNING: IEEEtran.bst: No hyphenation pattern has been}%
\typeout{** loaded for the language `#1'. Using the pattern for}%
\typeout{** the default language instead.}%
\else
\language=\csname l@#1\endcsname
\fi
#2}}
Just like in the other question I would like to use the bib style without changing the .bib file. However, the workaround/solution of the other question does not work with IEEEtran.
MWE (w/o the defunct workaround for natbib):
\begin{filecontents*}{\jobname.bib}
@inproceedings{Renyi1961,
author = {R\'{e}nyi, Alfr\'{e}d},
booktitle = {Proceedings of the Fourth Berkeley Symposium on Mathematical Statistics
and Probability, Volume 1: Contributions to the Theory of Statistics},
issn = {0097-0433},
language = {en},
publisher = {The Regents of the University of California},
title = {{On Measures of Entropy and Information}},
url = {http://projecteuclid.org/euclid.bsmsp/1200512181},
year = {1961}
}
\end{filecontents*}
\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[english]{babel}
\usepackage{hyperref}
\bibliographystyle{IEEEtran}
\begin{document}
\cite{Renyi1961}
\bibliography{\jobname}
\end{document}
enin the item will be exported aslangid = {english}. Would that make a change for your case? – retorquere Feb 23 '20 at 15:59languagefields that don't have their value processed AFAICT. – stefanct Feb 24 '20 at 05:41