 
The Joint Accelerator Conferences Website (JACoW) is an international collaboration that publishes the proceedings of accelerator conferences held around the world.
%\cite{yu:ipac2021-mopab041}
\bibitem{yu:ipac2021-mopab041}
   L.H. Yu, Y. Hao, Y. Hidaka, F. Plassard, and V.V. Smaluk,
   \textquotedblleft{Convergence Map with Action-Angle Variables Based on Square Matrix for Nonlinear Lattice Optimization}\textquotedblright,
% --- abbreviated form (published paper) - JACoW template Feb 2018 ---
   in \emph{Proc. IPAC'21}, Campinas, SP, Brazil, May 2021, pp. 182--185.
   \url{doi:10.18429/JACoW-IPAC2021-MOPAB041}
% --- additional material -ISSN/ISBN--
%  ISBN: 978-3-95450-214-1, ISSN: 2673-5490