Gaya APA

HOWELER, R, H. (1981). Mineral nutrition and fertilization of cassava (manihot esculenta crantz) . Colombia: Centro International de Agricultura Tropical.

Gaya MLA

HOWELER, R., H.. "Mineral nutrition and fertilization of cassava (manihot esculenta crantz)". Colombia: Centro International de Agricultura Tropical, 1981. Buku.