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\section{Test}

cite: \cite{Car1999} vs.~\cite[A]{Car1999} vs.~\cite[A][B]{Car1999}.

citep: \citep{Car1999} vs.~\citep[A]{Car1999} vs.~\citep[A][B]{Car1999}.

citealt: \citealt{Car1999} vs.~\citealt[A]{Car1999} vs.~\citealt[A][B]{Car1999}.

citealp: \citealp{Car1999} vs.~\citealp[A]{Car1999} vs.~\citealp[A][B]{Car1999}.

%citenum: \citenum{Car1999} vs.~\citenum[A]{Car1999} vs.~\citenum[A][B]{Car1999}.

citeauthor: \citeauthor{Car1999} vs.~\citeauthor[A]{Car1999} vs.~\citeauthor[A][B]{Car1999}.

citefullauthor: \citefullauthor{Car1999} vs.~\citefullauthor[A]{Car1999} vs.~\citefullauthor[A][B]{Car1999}.

citeyear: \citeyear{Car1999} vs.~\citeyear[A]{Car1999} vs.~\citeyear[A][B]{Car1999}.

citeyearpar: \citeyearpar{Car1999} vs.~\citeyearpar[A]{Car1999} vs.~\citeyearpar[A][B]{Car1999}.

cite: \cite{Beat1964}

cite*: \cite*{Beat1964}

citep: \citep{Beat1964}

citep*: \citep*{Beat1964}

citealt: \citealt{Beat1964}

citealt*: \citealt*{Beat1964}

citealp: \citealp{Beat1964}

citealp*: \citealp*{Beat1964}

citeauthor: \citeauthor{Beat1964}

citefullauthor: \citefullauthor{Beat1964}

\begin{thebibliography}{}
\bibitem[\protect\astroncite{Carlin}{1999}]{Car1999}
Carlin, G.: 1999,
\newblock {\em The Nature of My Stuff},
\newblock Some Publisher, Someplace
\bibitem[\protect\citeauthoryear{John, Paul, George and Ringo}{Beatles}{1964}]{Beat1964}
Beatles, The.: 1964,
\newblock {\em Help},
\newblock London, England
\end{thebibliography}
\end{document}
