Dawson and Trapp: Chapters 9, 10, 12.

Gum PA et al (2001) Aspirin use and all-cause mortality among patients being evaluated for known or suspected coronary artery disease: A propensity analysis.

Nicholas J, Gulliford MC (2008) Commentary: What is a propensity score?

Zweig MH, Campbell G (1993) Receiver-operating characteristic (ROC) plots: a fundamental evaluation tool in clinical medicine.

Wikipedia ROC curves.