%\cite{Feng:FEL2015-TUP056}
\bibitem{Feng:FEL2015-TUP056}
    Y.~Feng, J.T.~Delor, J.~Krzywinski, P.A.~Montanez, E.~Ortiz, T.O.~Raubenheimer, and M.~Rowen,
%   Y. Feng \emph{et al.},
   \textquotedblleft{Design Challenge and Strategy for the LCLS-II High Repetition Rate X-ray FEL Photon Stoppers}\textquotedblright,
%  in \emph{Proc. FEL2015}, TUP056, pp. 493--498,
%  in \emph{Proc. FEL2015}, Daejeon, Republic of Korea, August 2015, paper TUP056, pp. 493--498,
   in \emph{Proc. 37th International Free Electron Laser Conference (FEL2015)}, Daejeon, Republic of Korea, August 2015, paper TUP056, pp. 493--498,
    ISBN: 978-3-95450-134-2,
    \url{http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/tup056.pdf},
    doi:10.18429/JACoW-FEL2015-TUP056, 2015.