% The ``nat'' in ``natbib'' is for ``natural'' citations 

\documentclass{article}
\usepackage[numbers]{natbib}

\begin{document}
\section{Test}
Test paragraph. 

In recent work \cite{singleauthor}, \citeauthor{singleauthor} demonstrates something.

In recent work \cite{twoauthor}, \citeauthor{twoauthor} demonstrates something.

In recent work \cite{multiauthor}, \citeauthor{multiauthor} demonstrates something.


\bibliography{References}
%\bibliographystyle{plain}
\bibliographystyle{plainnat}  % MUST include this line or will get ``author undefined for citation'' errors
%\bibliographystyle{natbib} % this does not work

\end{document}
