Cita APA (7a ed.)

Engler, K. P., & Swanson, J. C. (1990). Animal welfare legislation and regulation: January 1979-august 1989. United States Department of Agriculture. National Agricultural Library.

Cita Chicago Style (17a ed.)

Engler, Kevin P., y Janice C. Swanson. Animal Welfare Legislation and Regulation: January 1979-august 1989. Beltsville (Maryland): United States Department of Agriculture. National Agricultural Library, 1990.

Cita MLA (9a ed.)

Engler, Kevin P., y Janice C. Swanson. Animal Welfare Legislation and Regulation: January 1979-august 1989. United States Department of Agriculture. National Agricultural Library, 1990.