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Visootsak J, Rosner B, Dykens E, Tartaglia N, Graham JM, Jr (2007). "Behavioral phenotype of sex chromosome aneuploidies: 48, XXYY, 48, XXXY, and 49,XXXXY". American Journal of Medical Genetics Part A. 143A (11): 1198–1203. doi:10.1002/ajmg.a.31746. PMID17497714. S2CID25732790.
Visootsak J, Rosner B, Dykens E, Tartaglia N, Graham JM, Jr (2007). "Behavioral phenotype of sex chromosome aneuploidies: 48, XXYY, 48, XXXY, and 49,XXXXY". American Journal of Medical Genetics Part A. 143A (11): 1198–1203. doi:10.1002/ajmg.a.31746. PMID17497714. S2CID25732790.