T. Vecchione,
   "Simulating Single Crystal Copper Photocathode Emittance",
   in Proc. 37th International Free Electron Laser Conference, Daejeon, Republic of Korea, August 2015, paper WEP002, pp. 587-591,
    ISBN: 978-3-95450-134-2,
    doi:10.18429/JACoW-FEL2015-WEP002,
    http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/wep002.pdf, 2015.