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Scheier M, Lachmann R, Pětroš M, Nicolaides KH.Scheier M, et al. Among authors: lachmann r.Ultrasound Obstet Gynecol. 2011 Dec;38(6):625-9. doi: 10.1002/uog.9067. Epub 2011 Nov 11.Ultrasound Obstet Gynecol. 2011.PMID: 21630364Free article.