Ngumy, J. G. (1992). Agroforestry in dryland Africa: Teacher's manual. Sweden: SIDA's Regional Soil Conservation Unit, RSCU.
Čikaški stil citiranjaNgumy, James G. Agroforestry in Dryland Africa: Teacher's Manual. Sweden: SIDA's Regional Soil Conservation Unit, RSCU, 1992.
MLA način citiranjaNgumy, James G. Agroforestry in Dryland Africa: Teacher's Manual. Sweden: SIDA's Regional Soil Conservation Unit, RSCU, 1992.
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