CASANUEVA, Esther, JIMÉNEZ, Julieta, MEZA-CAMACHO, Carlos et al. Prevalence of nutritional deficiencies in Mexican adolescent women with early and late prenatal care. ALAN. [online]. mar. 2003, vol.53, no.1 [citado 12 marzo de 2008], p.35-38. Disponible en la World Wide Web: [1]. ISSN 0004-0622.