1. P. Kofstad,Nonstoichiometry, Diffusion, and Electrical Conductivity in Binary Metal Oxides (Wiley Interscience, New York, 1972).
2. R. E. Carter and F. D. Richardson,J. Met. 7, 336 (1955).
3. S. Mrowec and K. Przybylski,Oxid. Met. 11, 365 (1977).
4. K. Przybylski, Ph.D. thesis,Academy of Mining and Metallurgy, Krak�w, Poland, 1976.
5. B. Fisher and D. S. Tannhauser,J. Chem. Phys. 44, 1663 (1966).