1. References to studies included in this review
2. Blakebrough 1983 {published data only}
3. Failure of meningococcal vaccination to stop the transmission of meningococci in Nigerian schoolboys;Blakebrough;Annals of Tropical Medicine and Parasitology,1983
4. Erwa 1973 {published data only}
5. A serogroup A meningococcal polysaccharide vaccine: studies in the Sudan to combat cerebrospinal meningitis caused by Neisseria meningitidis group A;Erwa;Bulletin of the World Health Organization,1973