# Why citet doesn't work in beamer?

I have a problem. Why 'citet' doesn't work in beamer?

\documentclass[11pt]{beamer}

\usepackage{indentfirst,multicol,amssymb}

\usepackage{booktabs,colortbl}

\usepackage[sort]{natbib}

\begin{document}

\begin{frame}

\frametitle{Books}

\begin{enumerate}

\item \citet{bra}
\end{enumerate}

\end{frame}
\bibliography{ref}
\end{document}


• What does 'doesn't work mean'? Do you get an error? – cfr Nov 18 '17 at 1:39
• Can you go back to your previous questions and look if the answers solve your problems and accept them, if they do? – user36296 Nov 18 '17 at 1:46

A \bibliographystyle is missing. For example:

\documentclass[11pt]{beamer}

\usepackage[sort]{natbib}

% to generate some dummy bib entry, as no one was in the question %%%%%%%%%%%%%%%%%%%%%%%
\usepackage{filecontents}
\begin{filecontents*}{\jobname.bib}
@book{knuth,
author       = {Knuth, Donald E.},
title        = {The {\TeX} book},
year         = 1984,
maintitle    = {Computers \& Typesetting},
volume       = {A},
langid       = {english},
langidopts   = {variant=american},
sortyear     = {1984-1},
sorttitle    = {Computers \& Typesetting A},
indexsorttitle= {The TeXbook},
indextitle   = {\protect\TeX book, The},
shorttitle   = {\TeX book}
}
\end{filecontents*}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}

\begin{frame}

\frametitle{Books}

\begin{enumerate}

\item \citet{knuth}
\end{enumerate}

\end{frame}

\begin{frame}
\bibliographystyle{abbrvnat}
\bibliography{\jobname}
\end{frame}

\end{document}


• Thanks for your help! I will try it. But actually I have more than one literature to be cited?! – Carl Nov 18 '17 at 1:57
• @Yang-Hui More bibitems are no problem. – user36296 Nov 18 '17 at 2:11
• But my bib document also contains other literature. Can I use my original bid file? Not create a new one? – Carl Nov 18 '17 at 2:13
• @Yang-Hui No problem. As the code you provided in the question did not contain any .bib entries, I was just too lacy to add more than one. – user36296 Nov 18 '17 at 2:15