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\newtheorem{thm}{Theorem}
\newtheorem{cor}{Corollary}

\begin{thm}
\label{brillig}
'Twas brillig, and the slithy toves
did gyre and gimble in the wabe.
\end{thm}

\begin{cor}
All mimsy were the borogoves,
and the mome raths outgrabe.
\end{cor}

\noindent{\sc Proof:} See Theorem \ref{brillig}.

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