1. N. N. Sirota, Physicochemical Nature of Phases with Variable Composition, Nauka i Tekhnika, Minsk (1970), 231 pp.
2. S. Metfessel and D. C. Mattis, Magnetic Semiconductors, Handbuch der Physic, Springer-Verlag, N. Y. (1968), 562 pp.
3. É. L. Nagaev, Physics of Magnetic Semiconductors, Nauka, Moscow (1979), p. 127.
4. R. von Helmholt, J. Wecker, B. Holzapfel, L. Shultz, and K. Samwer, Phys. Rev. Lett. 71, 2331 (1993); S. Jin, T. H. Tiefel, M. Mc. Cormack, R. A. Fasthnacht, R. Ramesh, and L. H. Chen, Science 264, 413 (1994).
5. V. A. Gavrichkov, S. G. Ovchinnikov, M. Sh. Erukhimov, I. S. Édel'man, and M. Sh. Erukhimov, Zh. Éksp. Teor. Fiz. 90, 1275 (1986) [Sov. Phys. JETP 63, 744 (1986)]; V. A. Gavrichkov, S. G. Ovchinnikov, and M. Sh. Erukhimov, Fiz. Tverd. Tela (Leningrad) 29, 527 (1987) [Sov. Phys. Solid State 29, 298 (1987)].