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Espinosa-Torres F, Hernández-Avila M, López-Carrillo L.Espinosa-Torres F, et al.Salud Publica Mex. 1994 Nov-Dec;36(6):597-616.Salud Publica Mex. 1994.PMID: 7892636Spanish.
López-Cervantes M, Salmerón-Castro J, López-Carrillo L, Hernández-Avila M, Schneider MC, Koiffman S.López-Cervantes M, et al.Salud Publica Mex. 1994 Mar-Apr;36(2):214-42.Salud Publica Mex. 1994.PMID: 8073338English, French, Portuguese, Spanish.No abstract available.