J. Hu, H.-S. Kang, and H.-S. Lee,
   "Development Activites Related to RF Cables for Good Phase Stability",
   in Proc. 37th International Free Electron Laser Conference, Daejeon, Republic of Korea, August 2015, paper WEP037, pp. 654-657,
    ISBN: 978-3-95450-134-2,
    doi:10.18429/JACoW-FEL2015-WEP037,
    http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/wep037.pdf, 2015.