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Gielen M, Derom C, Derom R, Vlietinck R, Zeegers MP.Gielen M, et al. Among authors: derom r.Twin Res Hum Genet. 2009 Apr;12(2):169-74. doi: 10.1375/twin.12.2.169.Twin Res Hum Genet. 2009.PMID: 19335187Free article.