I.I. Gadjev, C. Emma, A. Nause, and J.B. Rosenzweig,
   "High-Gain FEL in the Space-Charge Dominated Raman Limit",
   in Proc. 37th International Free Electron Laser Conference, Daejeon, Republic of Korea, August 2015, paper TUP008, pp. 347-350,
    ISBN: 978-3-95450-134-2,
    doi:10.18429/JACoW-FEL2015-TUP008,
    http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/tup008.pdf, 2015.