World Health Organization World Plumbing Council. (2006). Health aspects of plumbing. World health Organization.
Cita Chicago (17th ed.)World Health Organization World Plumbing Council. Health Aspects of Plumbing. Geneva: World health Organization, 2006.
Cita MLA (8th ed.)World Health Organization World Plumbing Council. Health Aspects of Plumbing. World health Organization, 2006.
Atenció: Aquestes cites poden no estar 100% correctes.