APA (7th ed.) Citation

Ernst, C. H., & Barbour, R. W. (1989). Turtles of the world. Smithsonian Institution Press.

Chicago Style (17th ed.) Citation

Ernst, Carl H., and Roger W. Barbour. Turtles of the World. Washington [etc.]: Smithsonian Institution Press, 1989.

MLA (9th ed.) Citation

Ernst, Carl H., and Roger W. Barbour. Turtles of the World. Smithsonian Institution Press, 1989.