Biometrika Cheng, J., Small, D., Tan, Z., and Ten Have, T.. Efficient nonparametric estimation of causal effects in randomized trials with noncompliance. Biometrika. 2009; 96:19-36. 2009 https://researcherprofiles.org/profile/1331890 Cheng, J., Small, D., Tan, Z., and Ten Have, T.