1. K. K. Likharev, Mikroélektronika 16, 195 (1987).
2. I. I. Abramov and E. G. Novik, Fiz. Tekh. Poluprovodn.(St. Petersburg) 33, 1388 (1999) [Semiconductors 33, 1254 (1999)].
3. O. I. Kulik and R. I. Shekhter, Zh. Éksp. Teor. Fiz. 68, 623 (1975) [Sov. Phys. JETP 41, 308 (1975)].
4. E. S. Demidov, Fiz. Tverd. Tela (St. Petersburg) 34, 37 (1992) [Sov. Phys. Solid State 34, 18 (1992)].
5. E. S. Demidov, in Proceedings of X Feofilov Symposium on Spectroscopy of Crystals, Activated Ions of Rare-Earth and Transition Metals (St. Petersburg, 1995), p. 97.