1. Davidson R. C.: Methods in Nonlinear Plasma Theory. Academic Press, New York, 1972.
2. Ott E., Sudan R. N.: Phys. Fluids12 (1969) 2388.
3. Geiss J., Balsiger H., Eberhardt P., Walker H. P., Weber L., Young D. T., Rosenbauer H.: Space Sci. Rev.22 (1978) 537.
4. Johnson R. G.: Rev. Geophys. Space Phys.17 (1979) 696.
5. Cornwall J. M., Schuiz M.:in Solar System Plasma Physics (ed. Kennal C. F., Lanzerotti L. J., Parker E. N.). North Holland, Amsterdam, 1979, Vol. 3, p. 165.