1. Yu. A. Izyumov, Usp. Fiz. Nauk 144, 439 (1984) [Sov. Phys. Usp. 27, 845 (1984)].
2. Y. Imry and S. Ma, Phys. Rev. Lett. 35, 1399 (1975).
3. E. B. Sonin, J. Phys. C 13, 3293 (1980).
4. A. A. Karaev, A. A. Leksikov, Yu. M. Fedorov, and V. V. Rudenko, in Proceedings of the XV All-Russia Workshop “Novel Magnetic Materials in Microelectronics”, Moscow, 1996, p. 455.
5. V. L. Preobrazhenskii, A. A. Shishkov, and N. A. Ékonomov, Fiz. Tverd. Tela (Leningrad) 29, 3549 (1987) [Sov. Phys. Solid State 29, 2034 (1987)].