This is puzzling, at least for me. I get a "! Missing \endcsname inserted" error in the following MWE:
\documentclass{article}
\usepackage[UKenglish,italian,french]{babel}
\usepackage{natbib}
\begin{document}
Hello world!~\cite{vim:2008}
\end{document}
If I remove the unbreakable space, or the french option from babel, or the colon from the citation, or the natbib package, everything works fine.
I'm compiling with pdflatex.
What can I do to make them work all together?
Best Answer
Load
natbib
beforebabel
.