1. Raka L, Mulliqi-Osmani G. Infection control in developing world; 2012. Available from: https://pdfs.semanticscholar.org/8703/b74aa2341cd2278202607367301764387a86.pdf. Accessed February 10, 2019.

2. Institute of Medicine (US) Committee for the Study of the Future of Public Health. The future of public health. Washington (DC): National Academies Press (US); 1988. 3. A History of the Public Health System. Available from: https://www.ncbi.nlm.nih.gov/books/NBK218224/. Accessed August 20, 2020.

3. On the global stability of a generalized cholera epidemiological model

4. A brief history of the prevention of infectious diseases by immunisations