1. Aarhus County, 1991. Randers Fjord 1990. Water Environmental Quality. 98 pp. (In Danish).
2. Aarhus County, 1992. Lake Knud 1990. State of pollution. 46 pp. (In Danish).
3. Andersen, J. M., 1982. Effect of nitrate concentration in lake water on phosphate release from sediment. Water Res. 16: 1119–1126.
4. Andersen, J. M. & J. Jensen, 1981. Correlation between degree of pollution and BOD in running waters. Vatten 81: 115–121.
5. Heise, P. B., 1984. Gudenaa. In: B. A. Whitton, Ecology of European Rivers. Blackwell, Oxford, 25–49.