@article{Dehejia2002,
author = {Dehejia, R.H. and Wahba, S.},
title= {Propensity score matching methods for nonexperimental causal studies},
year = {2002},
doi = {10.1162/003465302317331982},
journal = {Review of Economics and Statistics},
volume = {84},
number = {1},
pages = {151--161},
}