\documentclass{article}

\newcommand{\booktitle}[1]{\textit{#1}}
\def\mdash{\textemdash}
\def\amslatex{{\protect\AmS-\protect\LaTeX}}

\begin{document}

This is a test1 \cite{aaaaa}

\begin{thebibliography}{9}

\bibitem{aaaaa}Amer. Math. Soc., Providence, RI,
    1994; distributed with the AMSFonts package.

\bibitem{bbbbb}Amer. Math. Soc., Providence, RI,
    1995; distributed with the AMSFonts package.

\end{thebibliography}

\end{document}


-------execution------------------
> latex xxx.tex
> dvipdf xxx.dvi

\newcommand{\booktitle}[1]{\textit{#1}}
\def\mdash{\textemdash}
\def\amslatex{{\protect\AmS-\protect\LaTeX}}
は最初ないと[?]が出てしまうが一旦　.auxができるとこの3行がなくても[1]となる！！？？