American Journal of Obstetrics and Gynecology
American Journal of Obstetrics and Gynecology > 1996 > 175 > 2 > 484-488
American Journal of Obstetrics and Gynecology > 2005 > 193 > 1 > 267-272
American Journal of Obstetrics and Gynecology > 2007 > 196 > 5 > 480.e1-480.e6
American Journal of Obstetrics and Gynecology > 2014 > 211 > 3 > 237.e1-237.e13