APA引文

United States Department of Agriculture. (1981). USDA Grade Standards: For Food and Farm Products. Washington, D.C: United States Department of Agriculture.

Trích dẫn kiểu Chicago

United States Department of Agriculture. USDA Grade Standards: For Food and Farm Products. Washington, D.C: United States Department of Agriculture, 1981.

MLA引文

United States Department of Agriculture. USDA Grade Standards: For Food and Farm Products. Washington, D.C: United States Department of Agriculture, 1981.

警告：这些引文格式不一定是100％准确.