Igwe, J. C., and A. A. Abia. “Equilibrium Sorption Isotherm Studies of Cd(II), Pb(II) and Zn(II) Ions Detoxification from Waste Water Using Unmodified and EDTA-Modified Maize Husk”. Electronic Journal of Biotechnology, vol. 10, no. 4, Oct. 2007, pp. 0-0, https://preprints.pucv.cl/index.php/ejbiotechnology/article/view/v10n4-15.