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Sicras-Mainar A, Navarro-Artieda R; Grupo de estudio ACG-BSA.Sicras-Mainar A, et al.Gac Sanit. 2009 May-Jun;23(3):228-31. doi: 10.1016/j.gaceta.2008.04.005. Epub 2009 Mar 5.Gac Sanit. 2009.PMID: 19268402Free article.Spanish.