texのnatbibで, (hoge et al, 2030)みたいな引用

hoge.tex

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

\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
@article {Schimd1993,
author = {Schmid, Hans-Peter and McNeal, John E. and Stamey, Thomas A.},
title = {Observations on the doubling time of prostate cancer. The use of serial prostate-specific antigen in patients with untreated disease as a measure of increasing cancer volume},
journal = {Cancer},
volume = {71},
number = {6},
publisher = {Wiley Subscription Services, Inc., A Wiley Company},
issn = {1097-0142},
pages = {2031--2040},
keywords = {prostate cancer, serial prostate-specific antigen, doubling time, growth pattern},
year = {1993},
}
\end{filecontents}

\begin{document}

hoge \citep{Schimd1993}
  
\bibliographystyle{plainnat}
\bibliography{\jobname}

\end{document}