Cita APA (7a ed.)

Krebs, C. J. (1988). The message of ecology. Harper & Row.

Cita Chicago Style (17a ed.)

Krebs, Charles Joseph. The Message of Ecology. New York [etc.]: Harper & Row, 1988.

Cita MLA (9a ed.)

Krebs, Charles Joseph. The Message of Ecology. Harper & Row, 1988.