Não informado. (1962). Half-yearly progress report. West African Cocoa Research Institute.
Chicago-viite (17. p.)Não informado. Half-yearly Progress Report. Tafo, Gana: West African Cocoa Research Institute, 1962.
MLA-viite (8. p.)Não informado. Half-yearly Progress Report. West African Cocoa Research Institute, 1962.
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