H. Yang, H. Chung, B. Han, C. Jeon, Y.U. Jeong, K. Jung, and J. Kim,
   "Femtosecond Synchronization of 80-MHz Ti:Sapphire Photocathode Laser Oscillator with S-Band RF Oscillator",
   in Proc. 37th International Free Electron Laser Conference, Daejeon, Republic of Korea, August 2015, paper MOP036, pp. 105-106,
    ISBN: 978-3-95450-134-2,
    doi:10.18429/JACoW-FEL2015-MOP036,
    http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/mop036.pdf, 2015.