1. Phipps, D.A., Chemistry and biochemistry of trace metals in biological systems. in Effects of heavy metals in plants, N.W. Lepp (ed.), Applied Science Publishers.1, 1981.
2. Alloway, B.J., Heavy metals in soils. Blackie Publishers, London, 1995.
3. Jackson, A.P., and Alloway, B.J., The transfer of cadmium from agricultural soils to the human food chain. in Biogeochemistry of Trace Metals, D.C. Adriano (ed.) Lewis Publishers, Chelsea, Michigan, 109, 1992
4. Weber, W. J., Jr. and Mornes, J. C., Kinetics of adsorption on carbon from solutions, J. Sanitary Engineering, Div. Am. Civil Engr. 89, (2), 31, 1963.
5. Sajwan, K.S., Alva, A.K., and Keefer, R.F., Biogeochemistry of trace elements in coal and coal combustion by-products, Kluwer academic/Plenum Publishers. New York, 359, 1999.