Ginsburg, H., & Opper, S. (1969). Piaget's theory of intellectual development: An introduction. Prentice-Hall.
Chicago Style (17. basım) AtıfGinsburg, Herbert, ve Sylvia Opper. Piaget's Theory of Intellectual Development: An Introduction. Englewood Cliffs, N.J.: Prentice-Hall, 1969.
MLA (8th ed.) AtıfGinsburg, Herbert, ve Sylvia Opper. Piaget's Theory of Intellectual Development: An Introduction. Prentice-Hall, 1969.
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