1. H. Kroll, J. Am. Chem. Soc. 74:2036 (1952).
2. Q. Fernando, Advan. Inorg. Chem. Radiochem. 7:185 (1965).
3. R. W. Hay, Pure. Appl. Chem. 13:157 (1963).
4. R. W. Hay, J. Chem. Ed. 43:413 (1965).
5. M. M. Jones, “Ligand Reactivity and Catalysis”, Academic Press, New York (1968).