1. N. A. Torkhov, V. G. Bozhkov, I. V. Ivonin, and V. A. Novikov, Fiz. Tekh. Poluprovodn. 43, 38 (2009) [Semiconductors 43, 33 (2009)].
2. N. A. Torkhov and V. G. Bozhkov, Fiz. Tekh. Poluprovodn. 43(5) (2009) [Semiconductors 43, 551 (2009)].
3. N. A. Torkhov, Dep. v VINITI No. 32-B2008 from 14.01.2008 (Moscow, 2008).
4. V. G. Bozhkov, N. A. Torkhov, I. V. Ivonin, and V. A. Novikov, Fiz. Tekh. Poluprovodn. 42, 546 (2008)[Semiconductors 42, 531 (2008)].
5. N. L. Dmitruk, O. Yu. Borkovskaya, I. N. Dmitruk, et al., Appl. Surf. Sci. 190, 455 (2002).