1. Blaxter, J. H. S. 1970. Light: animals-fishes. pp. 213?285. In: O. Kinne (ed.) Marine Ecology, Vol. I, Environmental Factors, Part 1, Wiley, London.
2. Bo�tius, J. 1976. Elvers,Anguilla anguilla andAnguilla rostrata from two Danish localities. Size, body weight, development stage and number of vertebrae related to time of ascent Medd. Danm. Fisk.-Havunders. 7: 199?220.
3. Cushing, D. H. 1968. Fisheries biology. University of Wisconsin Press, Madison. 200 pp.
4. Heldt, M. & H. Heldt. 1929. Etudes sur les civelles de SidiDaoud. Bull. Stat. Oceanograph. Salammbo 16: 1?23.
5. Jespersen, P. 1942. Indo-Pacific leptocephalids of the genusAnguilla. Dana Rep. 22: 1?128.