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United Nations Environment and Development Report 2018. https://unstats.un.org/sdgs/report/2019/The-Sustainable-Develop- ment-Goals-Report-2019_Arabic.pdf
Numbeo is a new international report related to environmental pollution in the world of 2019. https://yallafeed.com/aldwl-alakthr-tl- wthaan-fy-alaalm-4867
