1. M.M. Mekonnen, A.Y. Hoekstra, Four billion people facing severe water scarcity, Sci. Adv., 2 (2016) e1500323.
  2. R. Roson, R. Damania, The macroeconomic impact of future water scarcity: an assessment of alternative scenarios, J. Policy Model., 39 (2017) 1141–1162.
  3. M.P. Radingoana, T. Dube, D. Mazvimavi, Progress in greywater reuse for home gardening: opportunities, perceptions and challenges, Phys. Chem. Earth Part A/B/C, 116 (2020) 102853.
  4. D.M. Ghaitidak, K.D. Yadav, Characteristics and treatment of greywater—a review, Environ. Sci. Pollut. Res. Int., 20 (2013) 2795–2809.
  5. A. Gross, A. Maimon, Y. Alfiya, E. Friedler, Greywater Reuse, Taylor & Francis Group, UK, 2015.
  6. O.R. Al-Jayyousi, Greywater reuse: towards sustainable water management, Desalination, 156 (2003) 181–192.
  7. S.S. Dalahmeh, L.D. Hylander, B. Vinnerås, M. Pell, I. Oborn, H. Jönsson, Potential of organic filter materials for treating greywater to achieve irrigation quality: a review, Water Sci. Technol., 63 (2011) 1832–1841.
  8. S.S. Dalahmeh, M. Pell, B. Vinnerås, L.D. Hylander, I. Öborn, H. Jönsson, Efficiency of bark, activated charcoal, foam and sand filters in reducing pollutants from greywater, Water Air Soil Pollut., 223 (2012) 3657–3671.
  9. Water Environment Federation (WEF), Clarifier Design, McGraw-Hill, USA, 2005.
  10. S.R. Qasim, G. Zhu, Wastewater Treatment and Reuse Theory and Design Examples, Vol. 1, Taylor & Francis Group, UK, 2011, pp. 725–730.
  11. G. Nakhla, S. Farooq, Simultaneous nitrification–denitrification in slow sand filters, J. Hazard. Mater., 96 (2003) 291–303.
  12. M. Spychala, R. Błazejewski, Sand filter clogging by septic tank effluent, Water Sci. Technol., 48 (2003) 153–159.
  13. K. Langenbach, P. Kuschk, H. Horn, M. Kästner, Slow sand filtration of secondary clarifier effluent for wastewater reuse, Environ. Sci. Technol., 43 (2009) 5896–5901.
  14. M. Spychala, H.T. Nguyen, Preliminary study on greywater treatment using nonwoven textile filters, Appl. Sci., 9 (2019) 3205.
  15. D. Hendricks, Fundamentals of Water Treatment Unit Processes: Physical, Chemical, and Biological, Taylor & Francis Group, UK, 2011.
  16. K. Riahi, A.B. Mammou, B.B. Thayer, Date-palm fibers media filters as a potential technology for tertiary domestic wastewater treatment, J. Hazard. Mater., 161 (2009) 608–613.
  17. T.H. Nguyen, R. Błażejewski, M. Spychała, Feasibility and economic efficiency of greywater reuse for plant irrigation, Ecol. Eng. (Polish), 19 (2018) 80–86.
  18. S.I.C. Ochoa, K. Ushijima, N. Hijikata, N. Funamizu, Treatment of domestic greywater by geotextile filter and intermittent sand filtration bioreactor, J. Water Reuse Desal., 5 (2014) 39–49.
  19. APHA/AWWA/WEF, Standard Methods for the Examination of Water and Wastewater, 22nd ed., American Public Health Association/American Water Works Association/Water Environment Federation, Washington, D.C., USA, 2012.
  20. P. Ridderstolpe, Introduction to Greywater Management, Ecosanres, WRS Uppsala AB, Sweden, 2004.
  21. M. Oteng-Peprah, N.K. de Vries, M.A. Acheampong, Greywater characterization and generation rates in a peri urban municipality of a developing country, J. Environ. Manage., 206 (2018) 498–506.
  22. M.S. Zipf, I.G. Pinheiro, M.G. Conegero, Simplified greywater treatment systems: slow filters of sand and slate waste followed by granular activated carbon, J. Environ. Manage., 176 (2016) 119–127.
  23. K. Chaillou, C. Gérente, Y. Andrès, D. Wolbert, Bathroom greywater characterization and potential treatments for reuse, Water Air Soil Pollut., 215 (2011) 31–42
  24. T. Buer, H. Herbst, M. Marggraff, Enhancement of Activated Sludge Plants by Lamella in Aeration Tanks and Secondary Clarifiers, In Nopon Aeration Conference on Applied Techniques to Optimise Nutrient Removal and Aeration Efficiency, Helsinki, Sweden, 2000, p. 7.
  25. H.I. Abdel-Shafy, M.A. El-Khateeb, M. Shehata, Greywater treatment using different designs of sand filters, Desal. Water Treat., 52 (2013) 5237–5242.
  26. C. Berger, Biochar and Activated Carbon Filters for GreyWater Treatment Comparison of Organic Matter and Nutrient Removal, Master Thesis, EnvEURO, Uppsala, Sweden, 2012.
  27. C.B. Niwagaba, P. Dinno, I. Wamala, S.S. Dalahmeh, C. Lalander, H. Jonsson, Experiences on the implementation of a pilot grey water treatment and reuse based system at a household in the slum of Kyebando-Kisalosalo, Kampala, J. Water Reuse Desal., 4 (2014) 294–307.
  28. C. Santos, F. Taveira-Pinto, C.Y. Cheng, D. Leite, Development of an experimental system for greywater reuse, Desalination, 285 (2012) 301–305.
  29. S.-J. Haig, C. Quince, R.L. Davies, C.C. Dorea, G. Collins, The relationship between microbial community evenness and function in slow sand filters, Am. Soc. Microbiol., 6 (2015) 1–12.
  30. F.Y. Li, K. Wichmann, R. Otterpohl, Review of the technological approaches for grey water treatment and reuses, Sci. Total Environ., 407 (2009) 3439–3449.
  31. E. Friedler, M. Hadari, Economic feasibility of on-site greywater reuse in multi-storey buildings, Desalination, 190 (2006) 221–234.