TY  - BOOK
AU  - Gruber,Howard E
AU  - Voneche,J.Jacques
TI  - The essential Piaget
SN  - 0710087780 :
U1  - 136.7 
PY  - 1977///
CY  - London
PB  - Routledge& Kegan Paul
KW  - Cognition in children
KW  - Knowledge, Theory of
KW  - Biology
N1  - Includes bibliographical references and index
ER  -