1. M. A. Zav’yalov and V. A. Syrovoi, Prikl. Fiz. 4, 44 (2004).
2. M. A. Zav’yalov and V. A. Syrovoi, High-Voltage Vacuum-Plasma Electronics. Collection Sci. Proc. VEI (VEI, Moscow, 2008), p.57.
3. Plasma Emission Electronics, Ed. by A. P. Semenov (Buryat. Nats. Tsentr Sib. Otd. RAN, Ulan-Ude, 2009; 2012; 2015). [in Russian].
4. M. A. Zav’yalov, Yu. E. Kreindel’, A. A. Novikov, and L. P. Shanturin, Plasma Processes in Technological Electron Guns (Energoatomizdat, Moscow, 1989).
5. I. Langmuir, Phys. Rev. 33, 954 (1929).