TY  - BOOK
AU  - Piaget, Jean
TI  - The child's conception of space
U1  - 155.4 
PY  - 1956///
CY  - London
PB  - Routledge and Kegan Paul, 
KW  - Premadasa Udagama Collection
KW  - E.L Wijemanna Collection
KW  - Differential and developmental psychology
ER  -