3. [No authors listed]. Appropriate technology for birth. Lancet 1985;2:436–7.
4. Department of Health and Human Services; Centers for Disease Control and Prevention; National Center for Health Statistics. Healthy People 2000: national health promotion and disease prevention objectives: Full report, with commentary (DHHS publication no. (PHS) 91–50212). Washington: Government Printing Office; 1990:378.
5. Robson MS. Classification of caesarean sections. Fetal and Maternal Medicine Review 2001;12(1):23–39.
6. Robson MS, Scudamore IW, Walsh SM. Using the medical audit cycle to reduce caesarean section rates. Am J Obstet Gynecol 1996;174(1):199–205.
7. Brennan DJ, Robson MS. Murphy M, O’Herlihy C. Comparative analysis of international cesarean delivery rates using 10-group classification identifies significant variation in spontaneous labor. Am J Obstet Gynecol 2009;201(3):308.e1–8.