1. Chromium
2. [2]. Clayton, G. D.; Clayton, F. E. (eds.) Pathy's Industrial Hygiene and Toxicology, 3rd edition, Wiley, New York, 1981, pp. 1658.
3. [3]. Herney, L. H. Trace Element Analytical Chemistry in Medicine and Biology, Pratter P. and Scharmel, P. (eds.), Vol. 3, Walter de Gruyter, Berlin, 1984, pp. 375.
4. [4]. Goyter, R. A.; Clarkson, T. W. Casarette and Doull's Toxicology: The Basic Science of Poisons, C. D. Klaassen (ed.), 6th edition, Macmillan Publishing Company, 2001, pp. 827.
5. VG Instruments, lnc.