Cita APA (7th ed.)

Keeton, W. T. (1973). Elements of biological science (2d ed.). Norton National Book Store.

Cita Chicago (17th ed.)

Keeton, William T. Elements of Biological Science. 2d ed. New York, Manila: Norton National Book Store, 1973.

Cita MLA (9th ed.)

Keeton, William T. Elements of Biological Science. 2d ed. Norton National Book Store, 1973.