@techreport{Centers for Disease Control and Prevention2014,
author = {Centers for Disease Control and Prevention},
title= {Appendix D: Contraceptive effectiveness},
year = {2014},
URL = {https://www.cdc.gov/mmwr/preview/mmwrhtml/rr6304a5.htm},
publisher = {Centers for Disease Control and Prevention},
institution = {Morbidity and Mortality Weekly Report},
}