APA (7th ed.) Citation

Hartley, R. E. b. (1952). Understanding children's play. Columbia University Press.

Chicago Style (17th ed.) Citation

Hartley, Ruth E. b.1909. Understanding Children's Play. New York: Columbia University Press, 1952.

MLA (9th ed.) Citation

Hartley, Ruth E. b.1909. Understanding Children's Play. Columbia University Press, 1952.