1. Sigel, H., Ed., Metal Ions in Biological Systems, Dekker, New York, 1974.
2. Eichorn, G.L., Ed., Inorganic Biochemistry, Elsevier, New York, 1973.
3. Hughes, M.N., The Inorganic Chemistry of Biological Processes, Wiley, New York, 1975.
4. Kruhoffer, P., Thaysen, J.H.,and Thorn, N.A., in: Handbuch der Experimentellen Pharmakologie, pp. 196, Springer-Verlag, Berlin, 1960.
5. Pressman, B.C., Harris, E.J., Jagger, W.S., and Johnson, J.H., Proc. Natl. Acad. Sei. U.S., 58: 1949, 1967.