Cita APA (7th ed.)

Johnson, P. H. (1968). The survival of the fittest. Macmillan.

Cita Chicago (17th ed.)

Johnson, Pamela Hansford. The Survival of the Fittest. London, Melbourne [etc.]: Macmillan, 1968.

Cita MLA (8th ed.)

Johnson, Pamela Hansford. The Survival of the Fittest. Macmillan, 1968.