1. Mandell GL, Bennett JE, Raphael. Mandell, Douglas, and Bennett's principles and practice of infectious diseases. 7th ed. USA: Churchill Livingstone/Elsevier; 2010. 4320 p.
2. Smeltzer C Suzanne, Brenda G Bare, Janice L Hinkle, et al. Brunner and Suddhart's Textbook of Medical-surgical Nursing. 11th ed. India: Wolters and kluwer; 2008.
3. Wei Sheng, Yan Jui, Robert Koch. Tuberculosis. Am J Respir Crit care Med. 2009;180:475–480.
4. Park K. Park's Textbook of preventive and social medicine. 18th ed. India: Banarsidas Bhanot Publishers; 2005. p. 1–4.
5. Department of health and population.