1. Boraas, M. E., 1983. Population dynamics of food limited rotifers in two stage chemostat culture. Limnol. Oceanogr. 27: 546?563.
2. Carpenter, R. L., 1978. Aquaculture as an alternative waste water treatment. In Pastakia C. M. R. (ed.), Fish farming and wastes. Report of the proceedings of an international conference held at the University College of London, 4?5 January 1978. London: 110?115.
3. Caulton, M. S., 1982. Feeding, metabolism and growth of tilapias: some quantitative considerations. In Pullin R. S. V. & R. H. Lowe-McConnell (eds), The biology and culture of tilapias. ICLARM. Manila, Phillipines: 157?183.
4. Dinges, R., 1982. Natural systems for water pollution control. van Nostrand Reinhold Environmental Engineering Series. New York. 252 pp.
5. Funke, J. W., J. G. Knoesen & J. C. Venter, 1984. Code of practice for the handling of manure from intensive animal feeding units. Water Research Commission, Pretoria. 42 pp.