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Engel M, Malta FM, Gomes MM, Mello IM, Pinho JR, Ono-Nita SK, Carrilho FJ.Engel M, et al.BMC Public Health. 2007 Apr 4;7:50. doi: 10.1186/1471-2458-7-50.BMC Public Health. 2007.PMID: 17408470Free PMC article.