APA (7e ed.) Bronvermelding

(1977). Soil fertility and research: The Philippines [microform]. Photoduplication Service.

Chicago (17e ed.) Bronvermelding

Soil Fertility and Research: The Philippines [microform]. Quezon City: Photoduplication Service, 1977.

MLA (9e ed.) Bronvermelding

Soil Fertility and Research: The Philippines [microform]. Photoduplication Service, 1977.

Let op: Deze citaties zijn niet altijd 100% accuraat.