1. The Sargasso Sea Eel Expedition 1979
2. C.E. Boyd, Water quality in warm water fish ponds. Agricultural Experiment Station, Auburn University, Auburn, AL, 1979, p. 359.
3. R.H. Aalderink, Analysis of the oxygen content in the Dutch surface water 1978 until 1989. Agricultural University Wageningen, Department of Nature Conservation, Section Waterquality, 1991.
4. A. Usui, Fishing News Books, Blackwell Scientific Publications Ltd, The University Press, Cambridge, ISBN 0-85238-182-4, 1991, 148 pp.