D.C, Washington Agriculture soil = Đất nông nghiệp Washington, D.C - 1st. - Amarican The Macmillan Company 1966 - 103p. 19cm. References: P. 94 - 104 Subjects--Topical Terms: Agriculture Subjects--Index Terms: Agriculture Soil Strycture Irrigation Oganic Fertilizer Cropping stystem Dewey Class. No.: 631.4 / A