1. Fisk,L.A.: 1979, in Solar System Plasma Physics, Eds. E.N. Parker, C.F. Kennel and L.J. Lanzerotti (North-Holland Publ. Co., New York ), p. 174.
2. Garcia-Munoz,M., Mason,G.M. and Simpson,J.A.: 1973, Ap. J. Lett., 257, L41.
3. Gloeckler,G.: 1979, Rev. Geophys. Sp. Phys., 17, p. 569.
4. McKibben, R.B., Pyle.K.R. and Simpson,J.A.: 1982, Ap. J. Lett., 257, p. L41.
5. Rochester,G.D. and Turver,K.E.: 1981, Contemp. Phys., 22, p. 425.