000 00329nam a2200121Ia 4500
001 84332
008 170722s9999 xx 000 0 und d
100 _aPiaget, Jean
245 _aChild's conception of number /
260 _c1941.
490 _aInternational library of psychology philosophy and scientific method
942 _cGEN
999 _c43032
_d43032