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Timpka T, Eriksson H, Gursky EA, Nyce JM, Morin M, Jenvald J, Strömgren M, Holm E, Ekberg J.Timpka T, et al.Bull World Health Organ. 2009 Apr;87(4):305-11. doi: 10.2471/blt.07.050203.Bull World Health Organ. 2009.PMID: 19551239Free PMC article.