WRIGHLEY, G. Tropical agriculture#the development of production#Gordon Wrighley. Longman.
Chicago-viite (17. p.)WRIGHLEY, Gordon. Tropical Agriculture#the Development of Production#Gordon Wrighley. Longman.
MLA-viite (8. p.)WRIGHLEY, Gordon. Tropical Agriculture#the Development of Production#Gordon Wrighley. Longman.
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