reduce font size of the character for the references in beamer

Question

I have a paper with all the references under \begin{thebibliography}{99} \end{thebibliography}

when I try to put many references either they have to come in several frames how can I shrink the size of the font just for the references?

Answer 1

This is one situation in which the evil allowframebreaks can be used:

\documentclass{beamer}

\begin{document}

\begin{frame}[allowframebreaks]
\begin{thebibliography}{99}
\bibitem{a} test
\end{thebibliography}
\end{frame}

\end{document}

If you want to reduce the font size, you can use any of the font size declarations:

\documentclass{beamer}

\begin{document}

\begin{frame}
\begin{thebibliography}{99}
\footnotesize
\bibitem{a} test
\end{thebibliography}
\end{frame}

\end{document}

I would suggest you not to change the font size (this provokes inconsistency). Another option (but I strongly suggest you not to use it) could be the evilest shrink option (refer to the beamer manual).