1. V. S. Vavilov, A. A. Gippius, and Zh. R. Panosyan, Cadmium Telluride [in Russian], Moscow (1968), p. 103.
2. V. Sermage and M. Voos, Phys. Rev. B,15, 3945 (1977).
3. M. S. Brodin and M. G. Matsko, Solid State Commun.,35, 375 (1980).
4. B. V. Novikov, A. B. Pavlov, and V. G. Talalaev, Fiz. Tverd. Tela,23, 207 (1981).
5. V. V. Travnikov and V. V. Krivolapchuk, Fiz. Tverd. Tela,24, 961 (1982).