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Cita Chicago (17th ed.)World Health Organization. Tools for Assessing the O&M Status of Water Supply and Sanitation in Developing Countries. Geneva: World Health Organization, 2000.
Cita MLA (8th ed.)World Health Organization. Tools for Assessing the O&M Status of Water Supply and Sanitation in Developing Countries. World Health Organization, 2000.
Atenció: Aquestes cites poden no estar 100% correctes.