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2. Wimpenny, R. S., Report on Fisheries., Egypt (1928).
3. Swynnerton, G. H., unpublished report on Lake Rukwa.
4. Fishery Resources of the United States. Document 51, 79th Congress, 1st Session (Washington, 1945).
5. Bertram, G. C. L., Empire J. Exp. Agric., 14, No. 56 (Oct. 1946).