这是并不是latex环境缺失什么的，而是要查看.tex中的参考文献部分。
常见的参考文献部分有如下两种。分别分析每种方式是否存在对应的问题即可。
参考文献方式 1
\bibliographystyle{plain}
\bibliography{mybibfile}
参考文献方式 2
\begin{thebibliography}{9}
\bibitem{Kempe03}
D.~Kempe, J.~Kleinberg, and E.~Tardos.
\newblock Maximizing the spread of influence through a social network.
\newblock In {\em Proc.
of the Ninth ACM Int. Conf. on Knowledge Discovery and
Data Mining (KDD’03)}.
\bibitem{Chen09}
W.~Chen, Y.~Wang, and S.~Yang.
\newblock Efficient influence
maximization in social networks.
\newblock In {\em Proc. of the 15th ACM
Int. Conf. on Knowledge Discovery and Data Mining
(KDD’09)}.
\end{thebibliography}