Piaget, J., Gruber, H. E., & Voneche, J. J. (1977). The essential Piaget. Basic Books.
Chicago Style (17th ed.) CitationPiaget, Jean, Howard E. Gruber, and J. Jacques Voneche. The Essential Piaget. New York: Basic Books, 1977.
MLA (9th ed.) CitationPiaget, Jean, et al. The Essential Piaget. Basic Books, 1977.
Warning: These citations may not always be 100% accurate.