1. 1. Calcott RD: Blindness in Kenya. Bulletin of the British Empire Society for the Blind 1956.
2. 2. Sinabulya PM: An assessment of the extent of blindness in Machakos district. East Afr Med J 1976; 53:63-73.
3. 3. Preliminary Results of 1979 Population Census. Government of Kenya Bureau of the Census 1981.
4. 4. Government of Kenya: Survey of Kenya. 1969.
5. 5. World Health Organization. The Prevention of Blindness. WHO Technical Report Series 1973 p 518.