Cita APA (7th ed.)

Purves, W. K., Sadava, D., Orians, G. H., & Heller, H. C. (2004). Life, the science of biology (Seventh Edition.). VHPS/W. H. Freeman.

Cita Chicago (17th ed.)

Purves, William K., David Sadava, Gordon H. Orians, i H. Craig Heller. Life, the Science of Biology. Seventh Edition. Gordonsville, VA U.S.A: VHPS/W. H. Freeman, 2004.

Cita MLA (9th ed.)

Purves, William K., et al. Life, the Science of Biology. Seventh Edition. VHPS/W. H. Freeman, 2004.