1. “Guidelines for Drinking-water Quality FOURTH EDITION INCORPORATING THE FIRST ADDENDUM.”
2. M. Österdahl, “Slow sand filtration as a water treatment method: An inventorying study of slow sand filters purification rates in rural areas in Colombia vattenreningsmetod,” p. 95, 2015, [Online]. Available: http://www.diva-portal.org/smash/get/diva2:839319/FULLTEXT01.pdf.
3. Slow sand filtration as a technique for the tertiary treatment of municipal sewages;ELLIS;Water Research,1987
4. Evaluation of roughing and slow sand filters for water treatment;El-Taweel;Water. Air. Soil Pollut.,2000
5. Biosand filter manual design, construction, installation, operation and maintenance;CAWST;Cent. Afford. Water Sanit. Technol.,2009