1. Karev, V. I., Korneev, V. V., Krutov, V. V., Lomkova, V. M., Oparin, S. N., Urnov, A. M., Vasilyev, B. N., Zhitnik, I. A., Gilvarg, A. B., and Belikova, T. S.: 1980, Preprint No. 81, P. N. Lebedev Physical Institute, Academy of Sciences of the USSR, Moscow.
2. Mewe, R. and Gronenschild, E. H. B. M.: 1981, Astron. Astrophys. Suppl. Ser. 45, 11.
3. Roussel-Dupree, R.: 1980a, Solar Phys. 68, 243.
4. Roussel-Dupree, R.: 1980b, Solar Phys. 68, 265.
5. Siarkowski, M., Sylwester, J., Bromboszcz, G., Korneev, V. V., Mandelshtam, S. L., Oparin, S. N., Urnov, A. M., Zhitnik, I. A., and Vasha, S.: 1982, Solar Phys. 77, 183.