by ENG, T. R, FISHBEIN, D. B, CARRASCO, J, ROBLES, A. R, BAER, G. M, TALAMANTE, H. E, HALL, D. B, CHAVEZ, G. F, DOBBINS, J. G, MURO, F. J, BUSTOS, J. L, DE LOS ANGELES RICARDY, M, MUNGUIA, A
Published in Bulletin of the World Health Organization (01.01.1993)