1. Recent trends in out-of-hospital births in the United States;MacDorman;J Midwifery Womens Health,2013
2. Osterman MJK Martin JA Curtin SC Newly released data from the revised birth certificate National Vital Statistics Reports
3. National Center for Health Statistics User's Guide to the 2014 Natality Public-Use Data Set ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/DVS/natality/UserGuide2014.pdf
4. Hamilton BE Martin JA Osterman MJK Births, final data for 2014
5. National Center for Health Statistics Guide to completing the facility worksheet for the certificate of live birth and report of fetal death http://www.cdc.gov/nchs/data/dvs/GuidetoCompleteFacilityWks.pdf