我在按章节拆分参考文献时遇到了麻烦。我尝试按照第一个答案进行操作对这个问题，因为它似乎最适合我的情况。但是，在我这样做之后，latex 找不到参考文献（引用未定义）。我没有发现我做错了什么。
这是一个可重现的示例，其中 Taylor_Herman_1971 参考不起作用：
\documentclass[12pt]{article}
\usepackage{multibib}
\newcites{vars}{Some title here for the second set of references}
\usepackage[round, sort]{natbib}
\date{\today}
\begin{document}
\section{First section}
Some text and two references \citep{Kriesi_Grande_Lachat_Dolezal_Bornschier_Frey_2008, Kriesi_Grande_Dolezal_Helbling_Hoglinger_Hutter_Wuest_2012}.
\bibliographystyle{chicago}
\bibliography{biblio_cee_appendix.bib}
\section{Second section}
Some other text and one new reference \citetvars{Taylor_Herman_1971}, as well as one of the old references \citepvars[][p. 364]{Kriesi_Grande_Lachat_Dolezal_Bornschier_Frey_2008}.
\bibliographyvars{biblio_cee_appendix.bib}
\end{document}
biblio_cee_appendix.bib 如下所示：
@book{Kriesi_Grande_Lachat_Dolezal_Bornschier_Frey_2008, address={New York:}, title={West European politics in the age of globalization}, ISBN={978-0-521-89557-6}, publisher={Cambridge University Press}, author={Kriesi, Hanspeter and Grande, Edgar and Lachat, Romain and Dolezal, Martin and Bornschier, Simon and Frey, Timotheos}, year={2008} }
@book{Kriesi_Grande_Dolezal_Helbling_Hoglinger_Hutter_Wuest_2012, address={Cambridge; New York}, title={Political Conflict in Western Europe}, ISBN={978-1-107-62594-5}, publisher={Cambridge University Press}, author={Kriesi, Hanspeter and Grande, Edgar and Dolezal, Martin and Helbling, Marc and Höglinger, Dominic and Hutter, Swen and Wüest, Bruno}, year={2012}, language={English} }
@article{Taylor_Herman_1971, title={Party Systems and Government Stability}, volume={65}, ISSN={0003-0554}, DOI={10.2307/1955041}, number={1}, journal={The American Political Science Review}, author={Taylor, Michael and Herman, V. M.}, year={1971}, pages={28–37} }