APA aipamena

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

Chicago Style aipamena

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

MLA aipamena

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

Kontuz: berrikusi erreferentzia hauek erabili aurretik.