1. A. K. Basu andF. R. Sale,Trans. Inst. Min. Metall. 86 (1977) C134.
2. Idem, ibid. 86 (1977) C169.
3. J. Guerassimov, Proceedings of the 16th IUPAC International Congress of Pure and Applied Chemistry Paris (Butterworth, London, 1957) p. 227.
4. P. Bracconi andL. C. Dufour,Met. Trans. 7B (1976) 321.
5. Idem, ibid. 7B (1976) 329.