World Health Organization. (2000). Tools for assessing the O&M status of water supply and sanitation in developing countries. World Health Organization.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)World Health Organization. Tools for Assessing the O&M Status of Water Supply and Sanitation in Developing Countries. Geneva: World Health Organization, 2000.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)World Health Organization. Tools for Assessing the O&M Status of Water Supply and Sanitation in Developing Countries. World Health Organization, 2000.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.