1. Alegre H. Hirner W. Baptista J. and Parena R. (2000). Manual of Best Practice. Performance Indicators for Water Supply Services. IWA Publishing.
2. Bourguett-Ortiz V. J. and Tzatchkov V. "Water utility performance indicators of Mexican cities" Proc. 4th IWA Specialist Conference on Efficient Use and Management of Urban Water Supply Jeju Korea 2007 1-8.
3. Deficiencies in drinking water distribution systems in developing countries
4. McIntosh A. C. and Yniguez C. (1997). Second Water Utilities Data Book: Asian and Pacific Region Asian Development Bank Manila.