1.
Salud pública Méx
; 39(3): 232-239, mayo-jun. 1997. tab
Article
in English
| LILACS
| ID: lil-217491
2.
Salud Publica Mex
; 39(1): 75-82, 1997.
Article
in Spanish
| MEDLINE
| ID: mdl-9092102