Cita APA (7th ed.)

Wolf, E. C. (1987). On the brink of extinction: Conserving the diversity of life. Worldwatch Institute.

Cita Chicago (17th ed.)

Wolf, Edward C. On the Brink of Extinction: Conserving the Diversity of Life. Washington, D.C.: Worldwatch Institute, 1987.

Cita MLA (8th ed.)

Wolf, Edward C. On the Brink of Extinction: Conserving the Diversity of Life. Worldwatch Institute, 1987.