1. U. Yutlo and R. Koén, Usp. Fiz. Nauk,109, No. 2, 371 (1973).
2. V. V. Belikovich, E. A. Benediktov, et al., Izv. Vyssh. Uchebn. Zaved., Radiofiz.,18, No. 4, 516 (1975).
3. V. A. Alebastrov, E. A. Benediktov, et al., Izv. Vyssh. Uchebn. Zaved., Radiofiz.,26, No. 4, 497 (1983).
4. I. F. Belov, E. A. Benediktov, et al., Abstracts of Papers, XIII All-Union Conference on Radiowave Propagation, Part 1, Nauka, Moscow (1981), p. 102.
5. Yu. A. Kravtsov and Yu. I. Orlov, Geometrical Optics of Inhomogeneous Media [in Russian], Nauka, Moscow (1980).