Não informado. (1962). Half-yearly progress report. West African Cocoa Research Institute.
Chicago-referens (17:e uppl.)Não informado. Half-yearly Progress Report. Tafo, Gana: West African Cocoa Research Institute, 1962.
MLA-referens (8:e uppl.)Não informado. Half-yearly Progress Report. West African Cocoa Research Institute, 1962.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.