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Hofmeyr GJ (June 2004). "Obstructed labor: using better technologies to reduce mortality". International Journal of Gynaecology and Obstetrics. 85 (Suppl 1): S62-72. doi:10.1016/j.ijgo.2004.01.011. PMID15147855. S2CID6981815.
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Evans KM, Adams VJ (2010). "Proportion of litters of purebred dogs born by caesarean section". Journal of Small Animal Practice. 51 (2): 113–8. doi:10.1111/j.1748-5827.2009.00902.x. PMID20136998.
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Khan KS, Wojdyla D, Say L, Gülmezoglu AM, Van Look PF (April 2006). "WHO analysis of causes of maternal death: a systematic review". Lancet. 367 (9516): 1066–1074. doi:10.1016/s0140-6736(06)68397-9. PMID16581405. S2CID2190885.