1. A. K. Awasthi and S. K. Upadhyay,Transition Met. Chem., in press.
2. F. Feigl,Spot Tests in Organic Analysis, Elsevier, London, 1960, p. 130, 214.
3. P. Fleury, J. Courtois and M. Grandchamp,Bull. Soc. Chim, Fr., 88 (1949).
4. F. E. Beasmish and J. C. Vanloon,Recent Advances in the Analytical Chemistry of Noble Metals, Pergamon Press, London, 1972, p. 465.
5. C. Surasiti and E. B. Sandell,Anal. Chem. Acta., 22, 261 (1960).