000 00267nam a2200109Ia 4500
100 _aChild Development; Vol 42
942 _cBK
654 _a
245 _aChild Development; Vol 42
_b1971
260 _aIllinois
_bUniversity of Chicago Press
_c1971
082 _a155.405
999 _c416746
_d416746
041 _aeng