World Health Organization. (2000). Tools for assessing the O&M status of water supply and sanitation in developing countries. World Health Organization.
Chicago-viite (17. p.)World Health Organization. Tools for Assessing the O&M Status of Water Supply and Sanitation in Developing Countries. Geneva: World Health Organization, 2000.
MLA-viite (8. p.)World Health Organization. Tools for Assessing the O&M Status of Water Supply and Sanitation in Developing Countries. World Health Organization, 2000.
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