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2. SOUTH AFRICAN SHIPPING NEWS AND FISHING INDUSTRY REVIEW 1969
3. ALVERSON, F.G., BULLETIN. INTER-AMERICAN-TROPICAL-TUNA-COMMISSION 7: 295 (1963).
4. BLACKBURN, M, OCEANOGRAPHY AND MARINE BIOLOGY: AN ANNUAL REVIEW 3: 299 (1965).
5. Upwelling and Fish Production;FAO FISHERIES TECHNICAL PAPER,1969