Wastewater treatment plants - Part 13: Chemical treatment; Treatment of wastewater by precipitation/flocculation; German version EN 12255-13:2002— 16 стр.
Small wastewater treatment systems for up to 50 PT - Part 3: Packaged and/or site assembled domestic wastewater treatment plants; German version EN 12566-3:2005— 48 стр.
Wastewater treatment plants - Principles for the design of structures and technical equipment - Part 3: Specific principles for the equipment for aerobical biological wastewater treatment— 28 стр.