1. Forstner, U., Calmano, W., Hong, J., & Kersten, M. (1998). Effects of redox variations on metal speciation. Waste Management and Research, 4, 95–104.
2. Fleeger, J.W., Carmana, K.R., & Nisbetb, R.M. (2003). Indirect effects of contaminants in aquatic ecosystem. The Science of Total Environment, 317(1–3), 207–233.
3. Helmke, P.A., Koons, R.D., Schomberg, P.J., & Iskander, I.K. (1995). Determination of trace element contamination of sediments by multielement analysis of clay–size fraction. Environmental Science of Technology, 10, 984–988.
4. Clarence, K., Jr. (1975). Infrared and Raman Spectroscopy of lunar and terrestrial minerals. New York: Academic Press, pp. 197–229.
5. Eletta, O.A.A. (2004). Physico–Chemical Characterization, Speciation and interaction studies of some pollutants in the water and sediments of Asa River, Ilorin. Nigeria. Ph.D thesis. University of Ilorin, Ilorin. Nigeria, pp. 235.