World Health Organization. (1994). Operation and Maintenance of Urban Water Supply and Sanitation Systems: A guide for managers. World Health Organization.
Цитирование в стиле Чикаго (17-е изд.)World Health Organization. Operation and Maintenance of Urban Water Supply and Sanitation Systems: A Guide for Managers. Switzerland: World Health Organization, 1994.
Цитирование MLA (9-е изд.)World Health Organization. Operation and Maintenance of Urban Water Supply and Sanitation Systems: A Guide for Managers. World Health Organization, 1994.
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