1. Rashba, E.I., Gurgenishvili, G.E.: Sov. Phys. Solid State 4 (1962) 759; Rashba, E.I.: Sov. Phys. Semicond. 8 (1975) 807.
2. Segall, B., Marple, D.T.F.: in: Aven, M., Prener, J.S. (eds.), Physics Chemistry II-VI Compounds, North Holl. (Amsterdam, Netherlands) 1967, p. 337.
3. Sanders, G.D., Chang, Y.: Phys. Rev. B 28 (1983) 5887.
4. Steiner, T., Thewalt, M.L.W., Bhargava, R.N.: Solid State Commun. 56 (1985) 933.
5. Kudlek, G., Hoffmann, A., Heitz, R., Fricke, C., Gutowski, J., Neumark, G.F., Bhargava, R.N.: J. Lumin. 48–49 (1991) 138.