1. D. E. Radley, J. Electron. Control 15, 469 (1963).
2. V. N. Danilov, Radiotekh. Elektron. (Moscow) 11, 1994 (1966).
3. P. T. Kirstein, G. S. Kino, and W. E. Waters, Space-Charge Flow (McGraw-Hill, New York, 1967; Mir, Moscow, 1970) [in Russian].
4. K. J. Harker, J. Math. Phys. 4, 993 (1963).
5. V. A. Syrovoi, Introduction to the Theory of Intense Charged-Particle Beams (Energoatomizdat, Moscow, 2004) [in Russian].