Y. Feng, M.L. Campell, J. Krzywinski, E. Ortiz, T.O. Raubenheimer, M. Rowen, and D.W. Schafer, "Measurment Uncertainties in Gas-Based Monitors for High Repetition Rate X-Ray FEL Operations", in Proc. 37th International Free Electron Laser Conference, Daejeon, Republic of Korea, August 2015, paper TUP026, pp. 417-421, ISBN: 978-3-95450-134-2, doi:10.18429/JACoW-FEL2015-TUP026, http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/tup026.pdf, 2015.