Ajah, P. O., and U. K. Enyenihi. “Phytoplankton As Rich Food for <i>Oreochromis niloticus</I> (LINN.) in Nigeria”. Tropical Freshwater Biology, vol. 16, no. 1, Dec. 2007, pp. 89-98, doi:10.4314/tfb.v16i1.20906.