Holbrook, BD; Phelan, ST (March 2013). “Umbilical cord prolapse.”. Obstetrics and Gynecology Clinics of North America40 (1): 1–14. doi:10.1016/j.ogc.2012.11.002. PMID23466132.
Holbrook, BD; Phelan, ST (March 2013). “Umbilical cord prolapse.”. Obstetrics and Gynecology Clinics of North America40 (1): 1–14. doi:10.1016/j.ogc.2012.11.002. PMID23466132.