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Haak MC, Bartelings MM, Gittenberger-De Groot AC, Van Vugt JM.Haak MC, et al. Among authors: van vugt jm.Ultrasound Obstet Gynecol. 2002 Jul;20(1):14-21. doi: 10.1046/j.1469-0705.2002.00739.x.Ultrasound Obstet Gynecol. 2002.PMID: 12100412Free article.