Olaifa, F., A. Olaifa, and T. Onwude. “Lethal and Sub-Lethal Effects of Copper to the African Catfish (<i>clarias gariepinus</I>) Juveniles”. African Journal of Biomedical Research, vol. 7, no. 2, Apr. 2010, doi:10.4314/ajbr.v7i2.54071.