1. The dissolved oxygen profile—A valuable tool for control of the activated sludge process;Olsson;Water Research,1987
2. Dissolved oxygen control in the activated sludge process;Olsson;Water Science Technology,1981
3. J.P. Stephenson, Practices in activated sludge process control, in: M.-Y. Murray (Ed.), Comprehensive Biotechnology, Pergamon Press, Oxford, England, 1985, pp. 1131–1144.
4. C.F. Lindberg, Control and estimation strategies applied to the activated sludge process. PhD dissertation, Uppsala University, 1997.
5. G. Olsson, Control strategies for the activated sludge process, In: M.-Y. Murray (Ed.), Comprehensive Biotechnology, Pergamon Press, Oxford, England, 1985, pp. 1107–1119.