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Vargas M, Gadelha CA, Costa LS, Maldonado J.Vargas M, et al.Rev Saude Publica. 2012 Dec;46 Suppl 1:37-40. doi: 10.1590/s0034-89102012000700006.Rev Saude Publica. 2012.PMID: 23532311Free article.Portuguese.