Update chapters/packages.tex

chapters/packages.tex

@@ -349,7 +349,7 @@ \section{Multilingual Descriptions}\label{multilingual-descriptions}
 The files to support translation must be provided along with the library.
 They must be stored in the resources directory \filename{modelica://$\mathit{LibraryName}$/Resources/Language/}.
 
-Two kind of files have to be provided:
+Two kind of files in \textcite{GettextManual} format have to be provided:
 \begin{enumerate}
 \item Template file \filename{$\mathit{LibraryName}$.pot}, as the resource \filename{modelica://$\mathit{LibraryName}$/Resources/Language/$\mathit{LibraryName}$.pot}.
 It contains all necessary information to translate all descriptions, but no translations.