Não informado. (2001). Pig improvement services. Meat and Livestock Commission.
Chicagoスタイル(17版)引用形式Não informado. Pig Improvement Services. Bletchley, Inglaterra: Meat and Livestock Commission, 2001.
MLA(8版)引用形式Não informado. Pig Improvement Services. Meat and Livestock Commission, 2001.
警告: この引用は必ずしも正確ではありません.