@article{McCaffrey2013,
author = {McCaffrey, D.F. and Griffin, B.A. and Almirall, D. and Slaughter, M.E. and Ramchand, R. and Burgette, L.F.},
title= {A tutorial on propensity score estimation for multiple treatments using generalized boosted models},
year = {2013},
doi = {10.1002/sim.5753},
volume = {32},
number = {19},
pages = {3388--3414},
}