1. Baker, D.E. (1990). Copper. In: Alloway, B.J. (Ed.) Heavy metals in soils. John Wiley and Sons, New York: 151-174.
2. Barber, S.A. (1984). Soil nutrient bioavailability – A mechanistic approach. John Wiley and Sons, New York.
3. Brown, J.C. (1978). Mechanisms of iron uptake in plants. Plant Cell and Environment, 1:249-257. https://doi.org/10.1111/j.1365-3040.1978.tb02037.x
4. Chaney, R.L. and Giordano, P.M. (1977). Soils for the management of organic wastes. In: Elliot, L.F. and Stevenson, f.J. (Ed.) Soil. Sci. Am. Soc. Agron & Crop Sci. Soc. Am. Maidson, 235-279.
5. Department of the Environment (1980). Inter-departmental Committee on the Re-development of Contaminated Land (ICRCL), Consultation paper, 2 Marshem Street, London.
6. Dolar, S.G. and Keeney, D.R. (1971). Availability of Cu, Zn and Mn in soils. Influence of soil pH, organic matter and extractable phosphorous. J. Sci. Fd. Agric., 22:273-287. https://doi.org/10.1002/jsfa.2740220602
7. Hannam, R.J. and Okhi, K. (1988). Manganese in soils and plants. In: Graham, R.R., Hannam, R.J. and Uren, N.C. (Ed.), Kluwer, Dordreent.
8. Kabata-Pendias, A. and Pendias, H. (1984). Trace elements in soils and plants. CRC Prerss, Boca Raton Fla.
9. Kiekens, L. (1990). Zinc. In: Alloway, B.J. (Ed.) Heavy metals in soils. John Willey and Sons, New York, 261-277.
10. Lindberg, S.E. and Harris, R.C. (1989). Water, Air and Soil Pollut. 16:13-31. https://doi.org/10.1007/BF01047039
11. Lindsay, W.L. (1979). Chemical Equilibria in Soils. John Wiley & Sons, New York.
12. Mc Larren, R.G. and Crawford, D.V. (1973). The specific adsorption of Cu by soils. J. Soil. Sci., 24443-452.
13. Ministry of Agriculture, Fisheries and Food (1982). The use of Sewage Sludge on agricultural land. Booklet 2409. HMSO, London.
14. Nriagu, J.O. (1978). The biogeochemistry of Lead in the environment, Elsevier, Armsterdam.
15. Schuhmacher, M.; Domingo, J.L.; Liobet, J.M. and Corbella, J. (1994). Cadmium, chromium, copper and zinc in rice and rice field soil from southern Catalonia, Spain, Bull. Environ. Contam. Toxicol., 53:54-60. https://doi.org/10.1007/BF00205138
16. Shim, S.C. and Vose, P.B. (1965). Varietal differences in the kinetics of iron uptake by excised rice roots. J. Expt. Bot., 16:216-232. https://doi.org/10.1093/jxb/16.2.216
17. Subramanyam, K. (1959). Observations on the flora of Boluvampatti forest, Coimbatore taluk, Bull. Bot. Sur. India 1:127-137. https://doi.org/10.20324/nelumbo/v1/1959/76656
18. Ure, A.M. and Berrow, M.L. (1982). The elemental constituents of soils. Environmental Chemistry, Vol. 2. Royal Society of Chemistry, London.