Cita APA (7th ed.)

Van Hoorn, J. L. (1993). Play at the center of the curriculum. Merrill.

Cita Chicago (17th ed.)

Van Hoorn, Judith Lieberman. Play at the Center of the Curriculum. New York: Merrill, 1993.

Cita MLA (9th ed.)

Van Hoorn, Judith Lieberman. Play at the Center of the Curriculum. Merrill, 1993.