1. Changes in Lake Norrviken after sewage diversion;Ahlgren;Verh. Internat. Verein. Limnol.,1972
2. Nitrification;Alexander,1965
3. Nitrogen and phosphorus budgets and the role of sediments in six shallow Danish lakes;Andersen;Arch. Hydrobiol.,1974
4. Nitrogen release from lake sediments;Austin;Jour. Water Poll. Control Fed.,1973
5. Bartholomew, W.V. and Clark, F.E. (Eds.) (1965): Soil Nitrogen. No. 10. Agronomy Ser., Amer. Soc. of Agronomy, Inc. Madison, USA. 615.