Mengenali Ciri-ciri Air yang Terkontaminasi Limbah dan Dampaknya pada Lingkungan

9. The Guardian. "Water Pollution: An Introduction." (https://www.theguardian.com/environment/2019/oct/23/water-pollution-an-introduction)

10. Environmental Pollution Centers. "Water Pollution: Causes, Effects, and Solutions." (https://www.environmentalpollutioncenters.org/water-pollution/)