Cita APA (7th ed.)
Zigler, E., & Hodapp, R. M. (1986). Understanding mental retardation. Cambridge University Press.
Cita Chicago (17th ed.)
Zigler, Edward, i Robert M. Hodapp. Understanding Mental Retardation. Cambridge ; New York: Cambridge University Press, 1986.
Cita MLA (9th ed.)
Zigler, Edward, i Robert M. Hodapp. Understanding Mental Retardation. Cambridge University Press, 1986.
Atenció: Aquestes cites poden no estar 100% correctes.