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Caamaño F, Figueiras A, Lado E, Gestal-Otero J.Caamaño F, et al.Gac Sanit. 2001 Nov-Dec;15(6):513-8. doi: 10.1016/s0213-9111(01)71614-7.Gac Sanit. 2001.PMID: 11858786Free article.Spanish.