1. A. G. Fischer: in Luminescence of Inorganic Solids, ed. by P. Goldberg (Academic Press, New York 1966) Chap. 10
2. M. Aven: II–VI Semiconducting Compounds, ed. by D. G. Thomas (Benjamin Publ. Co., New York 1967) p. 1232
3. F. F. Morehead: Physics and Chemistry of II–VI Compounds, ed. by M. Aven, J. S. Prener (North-Holland Publ. Co., Amsterdam 1967) p. 611
4. A. G. Fischer: Solid-State Electron. 2, 232 (1961)
5. A. G. Fischer: J. Electrochem. Soc. 118, 139C (1971)