@inbook{57220241,
author={Yi Yang},
editor={Yang, Yi and West-Strum, Donna},
title={Chapter 2. Principles of Epidemiology Applied to the Study of Medication Use},
booktitle={Understanding Pharmacoepidemiology},
publisher={The McGraw-Hill Companies},
address={New York, NY},
year={2011},
url={accesspharmacy.mhmedical.com/content.aspx?aid=57220241}
}