TY - BOOK ID - 127355026 TI - Logical thinking in children : research based on Piaget's theory AU - Sigel, Irving E. AU - Inhelder, Bärbel PY - 1968 PB - London : Holt, Rinehart and Winston, DB - UniCat UR - https://www.unicat.be/uniCat?func=search&query=sysid:127355026 AB - ER -