J.W. McKenzie, A.D. Brynes, and B.L. Militsyn,
   "Front End Simulations and Design for the CLARA FEL Test Facility",
   in Proc. 37th International Free Electron Laser Conference, Daejeon, Republic of Korea, August 2015, paper MOP057, pp. 171-175,
    ISBN: 978-3-95450-134-2,
    doi:10.18429/JACoW-FEL2015-MOP057,
    http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/mop057.pdf, 2015.