Treatment of water of swimming pools and baths – Part 4: Combinations of process with ultrafiltration
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 11/01/2012

Treatment of water of swimming pools and baths – Part 4: Combination of process: Flocculation, ozonisation, multilayer filtration, chlorination
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 02/01/1999