[1] Sigel, H., “Metal ions in biological systems”, 1, 37 edited by A Sigel (M Dekker, NY) (1971 – 1997); Williams, D.R., “The metals of Life” , Van Nostrand Rein Hold, New York (1971); “Transition metal sulfur chemistry, Biological and industrial significance”, edited by Stiefel, E.I., and Matsumoto, K., Oxford (2001).
[2] Leklem, J.E., “Handbook of Vitamins”, Marcel Decker Inc, New York, (1991); “Nutrition in Health and Disease”, Williams and Wilkins (1999).
[3] Karlin, K. D., and Tyeklar, Z., “Bioinorganic Chemistry”, Chapman and Hall, NewYork (1993).
[4] Nair, M.S., and Neelakantan, M.A., J. Indian Chem. Soc, 77, 373 (2000); 77, 394 (2000).
[5] Nair, M.S., Arasu, P.T., Pillai, M.S., and Natarajan, C., J. Chem. Soc. Dalton Trans, 917 (1993).
[6] Nair, M.S., Arasu, P.T., Pillai, M.S., and Natarajan, C., Trans Met. Chem, 1111 (1995).
[7] Nair, M.S., Arasu, P.T., Pillai, M.S., and Natarajan, C., Talanta, 40, 1411 (1993).
[8] Nair, M.S., and Neelakantan, M.A., Indian J. Chem, Sect. A, 38, 575 (1999).
[9] Gans, P., Vacca, A., and Sabatini, A., Inorg. Chim. Acta, 18, 23 (1976).
[10] El-Ezaby, M.S., and Al. Sogair, Polyhedron, 1, 791(1982); 2, 245 (1983).
[11] Chiacchierini, E., Ascenzo, G.D., De Angelis, G., Margi, A.L., and Peetrone, V., Ann. Chim(Rome), 67, 195 (1977).
[12] Shoukry, M. M., Khairy, E. M., and Mohamed, M.M., Talanta, 44, 1149 (1997).
[13] Sigel, H., Tribolet, R. B., and Yamuchi, O., Comments Inorg Chem, 9 (1990).
[14] Nakamoto, K., “Infrared and Raman Spectra of Inorganic and Coordination compounds”, John Wiely, New York (1978).