1. Busing, W. R...J. Chem. Phys., 1955,23, 933.
2. Krishnamurti, D...Proc. Ind. Acad. Sci., 1957,46 A, 183.
3. Krishnamurti, P...Ind. Jour. Phys., 1930,5, 651.
4. Mellor, J. W. ..A Comprehensive Treatise on Inorganic and Theoretical Chemistry, Longmans, Green & Co., 1946,2, pp. 502et seq.
5. Theimer, O...Mh. Chem., 1950,81, 301.