1. USEPA, WaterSentinel online water quality monitoring as an indicator of drinking water contamination, EPA 817-D-05–002, Washington, D.C., U.S. Environmental Protection Agency, Water Security Division, 2005, http://www.epa.gov/watersecurity/pubs/watersentinel_wq_monitoring.pdf, accessed 21 October 2014
2. W. F.
Boron
, Medical physiology: A cellular and molecular approach, Saunders/Elsevier, Philadelphia, PA, USA, 2003
3. WHO, Guidelines for drinking-water quality - Second edition - Volume 2-Health criteria and other supporting information, Geneva, 1996, http://www.who.int/water_sanitation_health/dwq/2edvol2p1.pdf, accessed 21 October 2014
4. Health Canada, Guidelines for Canadian drinking water quality: Chlorine, Authority of the Minister of Health, Ottawa, Canada, 2009, http://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/chlorine-chlore/index-eng.php, accessed 21 October 2014
5. USEPA, Nitrification, Office of Water, Washington, D.C., USA, 2002, http://water.epa.gov/lawsregs/rulesregs/sdwa/tcr/upload/nitrification.pdf, accessed 1 March 2015