1. B.A. Weber and S.M. Kulpa: Proceedings of the 4th International Conference on Ternary and Multinary Compounds, Tokyo, 1980, Japanese Journal of Applied Physics, Vol. 19, supplement 19-3 (1980) 345–348.
2. M.A. Kinch and B.V. Rollin, J.Appl. Phys. 14 (1963) 672.
3. Sh.M. Kogan, Sov. Phys. Sol. St. 4 (1963) 1813.
4. B.V. Rollin, Proc. Phys. Soc. London 77 (1961) 1102.
5. E.H. Putley, J. Phys. Chem. 22 (1961) 241.