Não informado. (1963). Half-yearly progress report. Cocoa Research Institute of Ghana.
Chicago-viite (17. p.)Não informado. Half-yearly Progress Report. Tafo, Gana: Cocoa Research Institute of Ghana, 1963.
MLA-viite (8. p.)Não informado. Half-yearly Progress Report. Cocoa Research Institute of Ghana, 1963.
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