Cita APA (7a ed.)

Smith, C. P., & Larson, J. (1990). Animal euthanasia. United States Department of Agriculture. National Agricultural Library.

Cita Chicago Style (17a ed.)

Smith, Cynthia Petrie, y Jean Larson. Animal Euthanasia. Beltsville (Maryland): United States Department of Agriculture. National Agricultural Library, 1990.

Cita MLA (9a ed.)

Smith, Cynthia Petrie, y Jean Larson. Animal Euthanasia. United States Department of Agriculture. National Agricultural Library, 1990.