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Bartels I, Hoppe-Sievert B, Bockel B, Herold S, Caesar J.Bartels I, et al. Among authors: herold s.Prenat Diagn. 1993 Feb;13(2):123-30. doi: 10.1002/pd.1970130207.Prenat Diagn. 1993.PMID: 7681977