1. Abramowitz, M., , I. A., Stegun, , Handbook of Mathematical Functions, Dover, New York, 1964,
2. Bellyustin, N. S., , V. P., Dokuchaev, , S. N., Polyakov, , V. V., Tamoikin, , Excitation of the Earth-Ionosphere Waveguide by Low Frequency Ionospheric Sources, Plenum, New York, 1976,
3. ELF communication by electrojet current modulation, internal report;Chang,1981
4. Method of remote sensing of horizontal stratification due to an ionospherically reflected powerful radio wave;Fejer;J. Geophys. Res.,1983
5. Nonlinear mixing in the ionosphere;Ganguly;Geophys. Res. Lett.,1986