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Bak GS, Shaffer BL, Madriago E, Allen A, Kelly B, Caughey AB, Pereira L.Bak GS, et al. Among authors: shaffer bl.Ultrasound Obstet Gynecol. 2020 Nov;56(5):705-716. doi: 10.1002/uog.21895.Ultrasound Obstet Gynecol. 2020.PMID: 31614030Free article.
Bak GS, Shaffer BL, Madriago E, Allen A, Kelly B, Caughey AB, Pereira L.Bak GS, et al. Among authors: shaffer bl.Ultrasound Obstet Gynecol. 2020 Jun;55(6):758-767. doi: 10.1002/uog.21977.Ultrasound Obstet Gynecol. 2020.PMID: 31945242Free article.