Citazione Stile APA (7a Edizione)

Beard, R. M. (2006). An outline of Piaget's development psychology. Routledge.

Citazione stile Chigago Style (17a edizione)

Beard, Ruth M. An Outline of Piaget's Development Psychology. London: Routledge, 2006.

Citatione MLA (9a ed.)

Beard, Ruth M. An Outline of Piaget's Development Psychology. Routledge, 2006.