1. Granatstein, V.L., Parker, R.K., Armstrong, C.M.: Vacuum electronics at the dawn of the twenty-first century. Proc. IEEE 187, 702–716 (1999)
2. Basu, B.N.: Electromagnetic Theory and Applications in Beam-Wave Electronics. World Scientific, Singapore (1996)
3. Kartikeyan, M.V., Borie, E., Thumm, M.K.A.: Gyrotrons High-Power Microwave and Millimeter Wave Technology. Springer, Germany (2004)
4. Sakamoto, K.: Gyrotron and millimeter wave technology. IEEE Trans. Plasma Sc. 34, 635–639 (2006)
5. Thumm, M.: History, Present and Future of Gyrotrons. International Vacuum Electronics Conference (IVEC – 2009), Rome, Italy (2009)