1. Aayog, N. (2018). Report of working group 1 inventory and revival of springs in the Himalayas for water security. https://niti.gov.in/writereaddata/files/document_publication/doc1.pdf.
2. Abdul Wahid, S. J. (2013). Water quality index of Delizhiyan springs and Shawrawa river within Soran district, Erbil, Kurdistan region of Iraq. Journal of Applied Environmental and Biological Sciences, 3(1), 40–48.
3. Ahsan, W. A., Ahmad, H. R., Farooqi, Z. U. R., Sabir, M., Ayub, M. A., Rizwan, M., & Ilic, P. (2021). Surface water quality assessment of Skardu springs using water quality index. Environmental Science and Pollution Research, 28, 20537–20548. https://doi.org/10.1007/s11356-020-11818-5
4. Ameen, H. A. (2019). Spring water quality assessment using water quality index in villages of Barwari Bala, Duhok, Kurdistan Region. Iraq. Applied Water Science, 9(8), 176. https://doi.org/10.1007/s13201-019-1080-z
5. American Public Health Association, American Water Works Association, Water Pollution Control Federation, & Water Environment Federation. (2017). Standard methods for the examination of water and wastewater (Vol. 23). London: American Public Health Association.