Não informado. (1937). Foreign agriculture. U.S. Department of Agriculture, Foreign Agricultural Service.
Chicago Style (17. basım) AtıfNão informado. Foreign Agriculture. Washington: U.S. Department of Agriculture, Foreign Agricultural Service, 1937.
MLA (8th ed.) AtıfNão informado. Foreign Agriculture. U.S. Department of Agriculture, Foreign Agricultural Service, 1937.
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