使用 \cite 命令的可选参数时，Beamer 出现错误

Question

\documentclass[presentation]{beamer}

\begin{document}

\begin{frame}
  \begin{example}[\cite[p. 42]{Author}]
    Nice example.
  \end{example}
\end{frame}

\begin{thebibliography}{1}

  \bibitem{Author}
    Author,
    Title,
    Publisher,
    2016.

\end{thebibliography}

\end{document}

编译上述文件时出现错误

$ pdflatex test.tex
Runaway argument?
p. 42)\fi \end {beamercolorbox}{\parskip 0pt
! Paragraph ended before \@citex was complete.
<to be read again> 
                   \par 

如果我[p. 42]从\cite命令中删除，错误就会消失。

如何在环境\cite的可选参数中使用命令的可选参数example？

$ pdflatex --version
pdfTeX 3.14159265-2.6-1.40.17 (TeX Live 2016)

Answer 1

尝试：

\documentclass[presentation]{beamer}

\begin{document}
\begin{frame}
  \begin{example}[{\cite[p. 42]{Author}}]% added {...}
    Nice example.
  \end{example}
\end{frame}

\begin{thebibliography}{1}
  \bibitem{Author}
    Author,
    Title,
    Publisher,
    2016.
\end{thebibliography}
\end{document}

[ ... ]不允许 嵌套在（任何）选项中。它必须位于花括号内，即{[...]}