1. M. V. Kuzelev and A. A. Rukhadze, Electrodynamics of Dense Electron Beams in Plasma (Nauka, Moscow, 1990) [in Russian].
2. L. S. Bogdankevich, M. V. Kuzelev, and A. A. Rukhadze, Usp. Fiz. Nauk 133, 3 (1981) [Sov. Phys. Usp. 24, 1 (1981)].
3. S. M. Levitskii and S. V. Koshevaya, Vacuum and Solid-State Microwave Electronics (Vyshcha Shkola, Kiev, 1986) [in Russian].
4. B. A. Aronov, L. S. Bogdankevich, and A. A. Rukhadze, in Plasma Chemistry, Ed. by B. M. Smirnov (Atomizdat, Moscow, 1975), Vol. 2, p. 245 [in Russian].
5. J. D. Lawson, The Physics of Charged-Particle Beams (Clarendon, Oxford, 1977; Mir, Moscow, 1980).