Responses of children immunized with capsular polysaccharide of Hemophilus influenzae type b, by David H. Smith, MD, et al, Pediatrics, 1973;52:637-644; and Haemophilus influenzae type b capsular polysaccharide vaccine in children: a double-blind field study of 100 000 vaccinees 3 months to 5 years of age in Finland, by Heikki Peltola, MD et al, Pediatrics, 1977;60:730-737.