1. Global Water Supply and Sanitation Assessment 2000 Report,2000
2. Taps and toilets for all—two decades already, and now a quarter century more;Mara;Water,2001
3. Hippocrates. On airs, waters and places (translated by Newman, JK, personal communication. Urbana-Champaign, IL, USA: University of Illinois; 1997).
4. Report on the sanitary condition of the labouring population of Great Britain;Chadwick,1842
5. On the Communication of Cholera;Snow,1855