Norman W Hudson. (1987). FAO soils bulletin N.57: Soil and water conservation in semi-arid areas. Rome: FAO.
Chicago Style aipamenaNorman W Hudson. FAO Soils Bulletin N.57: Soil and Water Conservation in Semi-arid Areas. Rome: FAO, 1987.
MLA aipamenaNorman W Hudson. FAO Soils Bulletin N.57: Soil and Water Conservation in Semi-arid Areas. Rome: FAO, 1987.
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