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2. N. I. Tarbaev, Fiz. Tverd. Tela (St. Petersburg) 40(10), 1845 (1998) [Phys. Solid State 40 (10), 1672 (1998)].
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4. I. V. Ostrovskii, L. P. Steblenko, and A. B. Nadtochii, Fiz. Tekh. Poluprovodn. (St. Petersburg) 34(3), 257 (2000) [Semiconductors 34 (3), 251 (2000)].
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