1. N. D. Sorokin, Yu. M. Tairov, V. F. Tsvetkov, and M. A. Chernov, Kristallografiya 28, 910 (1983) [Sov. Phys. Crystallogr. 28, 539 (1983)].
2. Yu. A. Vodakov, G. A. Lomakina, and E. N. Mokhov, Fiz. Tverd. Tela (Leningrad) 24, 1377 (1982) [Sov. Phys. Solid State 24, 780 (1982)].
3. A. A. Lebedev, Fiz. Tekh. Poluprovodn. (St. Petersburg) 33, 769 (1999) [Semiconductors 33, 707 (1999)].
4. R. G. Verenchikova, V. I. Sankin, and E. I. Radovanova, Fiz. Tekh. Poluprovodn. (Leningrad) 17, 1757 (1983) [Sov. Phys. Semicond. 17, 1123 (1983)].
5. S. Yu. Davydov, A. A. Lebedev, O. V. Posrednik, and Yu. M. Tairov, Fiz. Tekh. Poluprovodn. (St. Petersburg) 35, 1437 (2001) [Semiconductors 35, 1375 (2001)].