%\cite{Huang:FEL2015-TUB03}
\bibitem{Huang:FEL2015-TUB03}
    S.~Huang, Y.~Ding, Z.~Huang, and G.~Marcus,
   \textquotedblleft{Generating Femtosecond to Sub-Femtosecond X-Rays with a Modulated Chirped Beam in a Self-Seeded FEL}\textquotedblright,
%  presented at FEL2015, Daejeon, Republic of Korea, August 2015, paper TUB03, unpublished.
   presented at the 37th International Free Electron Laser Conference (FEL2015), Daejeon, Republic of Korea, August 2015, paper TUB03, unpublished.