1. Ostryakov, V.M. and Stovpyuk, M.F., Astron. Rep., 1997, vol. 41, p. 386.
2. Ruffolo, D., Ap. J., 1997, vol. 481, p. L119.
3. Barghouty, A.F. and Mewaldt, R.A., Ap. J., 1999, vol. 520, p. L127.
4. Kocharov, L., Kovaltsov, G.A., Torsti, J., et al., Astron. Astrophys., 2000, vol. 357, p. 716.
5. Kartavykh, Yu.Yu., Ostryakov, V.M., Stepanov, I.Yu., et al., Kosm. Issl., 1998, vol. 36, p. 465.