1. Department of Health. National tuberculosis control programme. Pretoria: Government Printers; 2011.
2. World Health Organization (WHO). WHO policy on TB infection controls in health care facilities, congregate settings and households. Geneva: WHO; 2009.
3. Kumar D. Research methodology: a step-by-step guide for beginners. 3rded. Washington: Sage; 2011.
4. O’Leary Z. The essential guide to doing research. London: Sage; 2004.
5. Tesch R. Qualitative research: analysis types and software tools. New York: The Falmer Press; 1994.