Cita APA (7a ed.)
Ginsburg, H. P., & Opper, S. Piaget's Theory of Intellectual Development. Prentice-Hall.
Cita estilo Chicago (17a ed.)
Ginsburg, Herbert P., y Sylvia Opper. Piaget's Theory of Intellectual Development. Englewood Cliffs, EUA: Prentice-Hall.
Cita MLA (9a ed.)
Ginsburg, Herbert P., y Sylvia Opper. Piaget's Theory of Intellectual Development. Prentice-Hall.
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