9Walker R, Turnbu11 D, Wilkinson C. Strategies to address global cesarean section rates: a review of the evidence[J]. Birth, 2002,29:28-39.
10Betrdn AP, Merialdi M, Lauer JA, et al. Rates of caesarean section: analysis of global, regional and national estimates[l]. Paediatr Perinat Epidemiol, 2007,21:98-113.