1. B. I. Shklovskii and A. L. Éfros, Electronic Properties of Doped Semiconductors (Nauka, Moscow, 1979; Springer, New York, 1984).
2. S. D. Baranovskii, B. I. Shklovskii, and A. L. Éfros, Zh. Éksp. Teor. Fiz. 78, 395 (1980) [Sov. Phys. JETP 51, 199 (1980)].
3. R. Chicon, M. Ortuño, and M. Pollak, Phys. Rev. B 37, 10520 (1988).
4. A. V. Dvurechenskii, A. V. Nenashev, and A. I. Yakimov, Nanotechnology 13, 75 (2002).
5. A. V. Nenashev, A. V. Dvurechenskii, and A. F. Zinovieva, Phys. Rev. B 67, 205301 (2003).