1. S. N. Mustafaeva and S. D. Mamedbeili, in Abstracts of the 9th International Conference on Ternary and Multinary Compounds, Yokohama, Japan (August 8–12, 1993), p. 281.
2. A. M. Darvish, A. É. Bakhyshov, and V. I. Tagirov, Fiz. Tekh. Poluprovodn. 11, 780 (1977) [Sov. Phys. Semicond. 11, 458 (1977)].
3. S. N. Mustafaeva, M. M. Asadov, and V. A. Ramazanzade, Fiz. Tverd. Tela (St. Petersburg) 38, 14 (1996) [Phys. Solid State 38, 7 (1996)].
4. N. F. Mott and E. A. Davis, Electronic Processes in Non-crystalline Materials [Clarendon Press, Oxford (1971); Russ. trans., Mir, Moscow (1974), 472 pp.].
5. V. Augelli, C. Manfredotti, R. Murri, R. Piccolo, and L. Vasanelli, Nuovo Cimento B 38, 327 (1977).