1. V. S. Berezinskii and O. F. Prilutskii, Astron. Astrophys., 175, 309–311 (1987)
2. J. Cooperstein, L. J. van der Horn, and E. Baron, Astrophys. J., 321, L129–L132 (1987).
3. É. A. Choban and A. N. Ivanov, Soviet JETP, 29, 109–111.
4. A. V. Borisov, V. Ch. Zhukovskii, and B. A. Lysov, Soviet Phys. J., 26, 701 (1983).
5. M. Yu. Knizhnikov and A. V. Tatarintsev, Moscow University Physics Bulletin, 25, 26–30 (1984).