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Romero M, Mondragón L, Cherpitel C, Medina-Mora ME, Borges G.Romero M, et al.Salud Publica Mex. 2001 Nov-Dec;43(6):537-43. doi: 10.1590/s0036-36342001000600004.Salud Publica Mex. 2001.PMID: 11816228