1. Avduyevsky, V. S., Marov, M. Ja., and Rojdestvensky, M. K.: 1969, Kosmich. Issled. 7, 2, 233.
2. Axford, W. I.: 1968, J. Geophys. Res. 73, 6855.
3. Axford, W. I.: 1969, Rev. Geophys. 7, 1–2, 421.
4. Barth, C. A., Wallace, L., and Pearce, J. B.: 1968, J. Geophys. Res. 73, 7, 2541.
5. Bezrukikh, V. V.: 1969, Paper presented to the International Symposium on the Physics of the Magnetosphere, Washington, September 1969, Kosmich. Issled.