1. Bounding a matching estimator: the case of a Norwegian training program;Aakvik;Oxford Bulletin of Economics and Statistics,2001
2. Gynecologic oncology or medical oncology: What's in a name;Cannistra;Journal of Clinical Oncology,2007
3. Local sensitivity approximations for selectivity bias;Copas;Journal of the Royal Statistical Society B,2001
4. Smoking and lung cancer;Cornfield;Journal of the National Cancer Institute,1959
5. Randomization in the design of experiments;Cox;International Statistical Review,2009