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noindent Changing\
Lamport (1994, 12-30) into\
citet[12-30]{lamport94}

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  providecommand{doi}[1]{doi: #1}else
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bibitem[Lamport(1994)]{lamport94}
Leslie Lamport,
emph{LaTeX: A Document Preparation System}.
Addison Wesley, Massachusetts,
2nd Edition,
1994.
end{thebibliography}
end{document}