1. V. L. Ginzburg and A. V. Gurevich, Usp. Fiz. Nauk,70, 201, 393 (1960).
2. D. T. Farley, J. Geophys. Res.,68, 401 (1963).
3. P. V. Bliokh and A. S. Bryukhovetskii, Geomagn. Aeron.,9, 545 (1969).
4. A. V. Gurevich, Geomagn. Aeron.,12, 24 (1972).
5. A. V. Gurevich and A. B. Shvartsburg, Nonlinear Theory of Radio-Wave Propagation in the Ionosphere [in Russian], Izd. Nauka, Moscow (1973).