000 00507nam a2200157Ia 4500
008 131223s9999 xx 000 0 und d
040 _aISI KOLKATA
041 _aEnglish
082 _a371.26
_bRb-72-39
100 _aRubin Donald
245 _aEstimating casual effects of treatments in experimental and observational studies
260 _aNew Jersey
_bETS
_c1972
440 _aEducational Testing Service. Princeton : Research bulletin; 39
650 _aEducational tests and measurements
942 _cBK
999 _c81905
_d81905