1. R. Morineau, Phys. Status Solidis (a),38, 559 (1976).
2. A. N. Men', M. P. Bogdanovich, Yu. P. Vorob'ev, R. Yu. Dobrovinskii, V. M. Kamyshov, and V. B. Fetisov, Composition-Defects-Property of Solid Phases [in Russian], Nauka, Moscow (1977), p. 284.
3. F. K. Lotgering and A. M. van Diepen, J. Phys. Chem. Sol.,34, No. 8, 1369 (1973).
4. A. N. Men', and A. P. Orlov, Fiz. Met. Metalloved.,1, No. 3, 110 (1955).
5. H. B. Callen, S. Harrison, and C. J. Krissman, Phys. Rev.,103, 856 (1956).