John Andrew David David, J., Ives, R. L., Tran, H. T., Bui, T., & Read, M. E. (2008). Computer optimized design of electron guns. IEEE TRANSACTIONS ON PLASMA SCIENCE, 36(1), 156–168. https://doi.org/10.1109/TPS.2007.913884 David, J. A., Kory, C. L., Tran, H. T., Ives, R. L., & Chernin, D. (2007). Enhanced features for design of traveling wave tubes using CHRISTINE-1D. IEEE TRANSACTIONS ON PLASMA SCIENCE, 35(4), 1056–1064. https://doi.org/10.1109/TPS.2007.902128