%\cite{Niknejadi:FEL2015-WEP079} \bibitem{Niknejadi:FEL2015-WEP079} P.~NiknejadiJ.~Madey, \textquotedblleft{Inclusion of Advanced Fields and Boundary Conditions in the Analytic Theory for High Gain FELs}\textquotedblright, % in \emph{Proc. FEL2015}, WEP079, pp. 735--738, % in \emph{Proc. FEL2015}, Daejeon, Republic of Korea, August 2015, paper WEP079, pp. 735--738, in \emph{Proc. 37th International Free Electron Laser Conference (FEL2015)}, Daejeon, Republic of Korea, August 2015, paper WEP079, pp. 735--738, ISBN: 978-3-95450-134-2, \url{http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/wep079.pdf}, doi:10.18429/JACoW-FEL2015-WEP079, 2015.