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Molina Siguero A, García Pérez MA, Alonso González M, Cecilia Cermeño P.Molina Siguero A, et al.Aten Primaria. 2003 May 31;31(9):564-71. doi: 10.1016/s0212-6567(03)79217-8.Aten Primaria. 2003.PMID: 12783745Free PMC article.Spanish.