APA ציטוט

U.S. Soil Conservation Service. (1939). Conservation of the soil; a unit for elementary schools developed by the Fairbrother-Rossell School, in cooperation with the Soil Conservation Service, USDA. s.n.

Chicago Style (17th ed.) Citation

U.S. Soil Conservation Service. Conservation of the Soil; a Unit for Elementary Schools Developed by the Fairbrother-Rossell School, in Cooperation with the Soil Conservation Service, USDA. Washington, D. C: s.n, 1939.

ציטוט MLA

U.S. Soil Conservation Service. Conservation of the Soil; a Unit for Elementary Schools Developed by the Fairbrother-Rossell School, in Cooperation with the Soil Conservation Service, USDA. s.n, 1939.