Christy, L. C. (1972). Legislative principles of soil conservation. Food and Agriculture Organization of the United Nations.
Dyfyniad Arddull ChicagoChristy, Lawrence C. Legislative Principles of Soil Conservation. Rome: Food and Agriculture Organization of the United Nations, 1972.
Dyfyniad MLAChristy, Lawrence C. Legislative Principles of Soil Conservation. Food and Agriculture Organization of the United Nations, 1972.
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