Cita APA

Putman, R. J., & Wratten, S. D. (1984). Principles of ecology. Croom Helm.

Citación estilo Chicago

Putman, R. J., and S. D. Wratten. Principles of Ecology. London: Croom Helm, 1984.

Cita MLA

Putman, R. J., and S. D. Wratten. Principles of Ecology. Croom Helm, 1984.