1. A. G. Rokakh, A. G. Zhukov, A. A. Serdobintsev, and S. V. Stetsyura, in Semiconductor Physics and Semiconductor Electronics (Kolledzh, Saratov, 2001), p. 56 [in Russian].
2. A. G. Rokakh, S. V. Stetsyura, and A. A. Serdobintsev, Izv. Vyssh. Uchebn. Zaved., Prikl. Nelin. Dinam. 14, 113 (2006); A. G. Rokakh and M. D. Matasov, Semiconductors 44, 98 (2010).
3. T. A. Vartanyan, E. V. Vashchenko, N. B. Leonov, et al., J. Exp. Theor. Phys. 109, 140 (2009).
4. A. M. Filachev, I. I. Taubkin, and M. A. Trishenkov, Solid State Photoelectronics. Physical Principles (Fizmatkniga, Moscow, 2005), p. 33 [in Russian].
5. A. G. Rokakh and N. B. Kats, Sov. Tech. Phys. Lett. 5, 2 (1979).