Cita APA

Purves, W., & Orians, G. (1987). Life the science of biology (2 ed.). Massachusetts :: Sinauer Associates Inc.,.

Citación estilo Chicago

Purves, W., y G.H Orians. Life the Science of Biology. 2 ed. Massachusetts :: Sinauer Associates Inc.,, 1987.

Cita MLA

Purves, W., y G.H Orians. Life the Science of Biology. 2 ed. Massachusetts :: Sinauer Associates Inc.,, 1987.