1. Mitra, A.P., [The solar flares influence on the Earth ionosphere], Mir, Moscow, 15–22 (1977).
2. Wait, J.R., [Electromagnetic waves in stratified media], Pergamum, New York, (1970).
3. Manifestation SID at high latitude paths;Demykin,1982
4. Latitudinal dependence of the effective electron-loss coefficient in the daytime lower ionosphere as deduced from VLF phase variations and riometric absorption data during SIDs;Orlov,1998
5. Belenky, M.I., Orlov, A.B., Pronin, A.E., Uvarov, A.N., “About dependence of the SPA VLF from the solar zenith angle on long paths on different latitudes,” Proc. VIII Regional Conference of Radio Wave Propagation. St. Petersburg, 25 (2002).