Matching by propensity score in cohort studies with three treatment groups
Epidemiology (2013) - Comments
pubmed: 23532053  doi: 10.1097/ede.0b013e318289dedf  issn: 1531-5487  issn: 1044-3983 

Jeremy A. Rassen, Abhi A. Shelat, Jessica M. Franklin, Robert J. Glynn, Daniel H. Solomon, Sebastian Schneeweiss