1. Abunin, A.A., Abunina, M.A., Belov, A.V., Eroshenko, E.A., Oleneva, V.A., Yanke, V.G.: 2012, Geomagn. Aeron. 52, 292.
2. Abunin, A.A., Abunina, M.A., Belov, A.V., Eroshenko, E.A., Oleneva, V.A., Yanke, V.G., Mavromichalaki, H., Papaioannou, A.: 2013 In: Proc. 33rd Int. Cosmic Ray Conf., id-198.
3. Abunina, M.A., Abunin, A.A., Belov, A.B., Eroshenko, E.A., Asipenka, A.C., Oleneva, V.A., Yanke, V.G.: 2013, Geomagn. Aeron. 53, 13.
4. Badruddin, Y.R.S., Yadav, N.R.: 1986, Solar Phys. 105, 413.
5. Barnden, L.R.: 1973 In: Proc. 13th Int. Cosmic Ray Conf. 2, 1277.