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Tchirikov M, Schlabritz-Loutsevitch N, Nathanielsz PW, Beindorff N, Schröder HJ.Tchirikov M, et al.Ultrasound Obstet Gynecol. 2005 Sep;26(3):252-7. doi: 10.1002/uog.1973.Ultrasound Obstet Gynecol. 2005.PMID: 16116564Free article.