User, A. (2018). NATURAL WATER HARDNESS, POLLUTION, WATER CYCLE, TREATMENT AND USES. Afribary. Retrieved from https://afribary.com/works/natural-water-hardness-pollution-water-cycle-treatment-and-uses
User, Anonymous "NATURAL WATER HARDNESS, POLLUTION, WATER CYCLE, TREATMENT AND USES" Afribary. Afribary, 03 Feb. 2018, https://afribary.com/works/natural-water-hardness-pollution-water-cycle-treatment-and-uses. Accessed 28 May. 2022.
User, Anonymous . "NATURAL WATER HARDNESS, POLLUTION, WATER CYCLE, TREATMENT AND USES". Afribary, Afribary, 03 Feb. 2018. Web. 28 May. 2022. < https://afribary.com/works/natural-water-hardness-pollution-water-cycle-treatment-and-uses >.
User, Anonymous . "NATURAL WATER HARDNESS, POLLUTION, WATER CYCLE, TREATMENT AND USES" Afribary (2018). Accessed May 28, 2022. https://afribary.com/works/natural-water-hardness-pollution-water-cycle-treatment-and-uses