1. Luck, W. and Wehling, B. 1984. 33éme Cong Annuel de l'Association Quimica Espanola de la Industria del Cuero. 1984, Spain. pp.33–39. Marbella.
2. Recovery of chromium from tannery effluents using a redox-adsorption approach
3. NRC. Associate Committe on Scientific Criteria for Environmental Quality. 1977. “The effects of chromium in the Canadian Environment”. Publication No. 15018
4. Dean, R. B. and Lund, E. 1981.Water Reuse, 31London: Academic Press.