1. L. D. Landau and E. M. Lifshits, Electrodynamics of Continuous Media [in Russian], Moscow (1957).
2. S. N. Lasarov, A. A. Homic, T. V. Ljashko, and V. V. Lapinsky, ?Some thermodynamical characteristics of polyethylene crystallized in impulse magnetic field,? Bolg. Fiz. Zh.,15, No. 6, 600?608 (1988).
3. S. N. Lazarov, V. L. Velev, and N. P. Nikolov, ?Thermomagnetic modification of polyethylene,? Nauch. Tr. Plovdiv. Universitet, Fiz.,24, No. 1, 75?82 (1986).
4. S. V. Vonsovskii, Magnetism [in Russian], Moscow (1971).
5. M. V. Vol'kenshtein, Molecular Optics [in Russian], Leningrad (1951).