S. Chen, K. Ohmi, and D. Zhou,
   "Coherent Thomson Scattering Using the PEHG",
   in Proc. 37th International Free Electron Laser Conference, Daejeon, Republic of Korea, August 2015, paper TUP009, pp. 351-353,
    ISBN: 978-3-95450-134-2,
    doi:10.18429/JACoW-FEL2015-TUP009,
    http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/tup009.pdf, 2015.