1. A. A. Kal'fa, S. B. Poresh, and A. S. Tager, Reviews in Electronics. Series on Microwave Electronics [in Russian], Central Scientific-Research Institute of Electronics, Moscow (1984), No. 4.
2. V. Denis, Zh. Kantsleris, and Z. Martunas, Electrons in Semiconductors. Warm Electrons [in Russian], Vol. 4, Mokslas, Vilnius (1983), p. 90.
3. M. Costato, S. Fontanesi, and L. Reggiani, J. Phys. Chem. Solids,34, No. 3, 547 (1973).
4. F. Zaifert, Proc. IEEE,53, No. 7, 866 (1965).
5. S. V. Plaksin, L. M. Pogorelaya, V. N. Privalov, and I. I. Sokolovskii, Development of Elements for Hybrid Integrated Circuits for the Optical and Millimeter Ranges [in Russian], Tula Polytechnic Institute (1985), p. 50.