1. Kinetics of biochemical nitrification and denitrification;Balakrishnan,1968
2. Optimale Stickstoff-Abgasung durch Einsatz von Nitrifizierendem Belebtschlamm und Redox-Steurung;Bringmann;Gesundeits-ingenieur,1960
3. Complete biological elimination of nitrogen from clarified sewage in conjunction with a high efficiency nitrification process;Bringmann;Gesundheits-ingenieur,1961
4. Model experiments on the biological removal of nitrogen as gas from treated sewage;Bringmann;Gesundeits-ingenieur,1959