H. Jeevakhan, G. Mishra, and P.K. Purohit,
   "Influence of Horizantal Constant Magnetic Field on Harmonic Undulator Radiations and Gain",
   in Proc. 37th International Free Electron Laser Conference, Daejeon, Republic of Korea, August 2015, paper MOP004, pp. 34-37,
    ISBN: 978-3-95450-134-2,
    doi:10.18429/JACoW-FEL2015-MOP004,
    http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/mop004.pdf, 2015.