TY  - JOUR
A1  - Heckman, J. J.
A1  - Robb, R.
T1  - Alternative methods for evaluating the impact of interventions: An overview
Y1  - 1985
DO  - 10.1016/0304-4076(85)90139-3
JF  - Journal of Econometrics
VL  - 30
IS  - 1
SP  - 239
EP  - -267

ER  -