1. The Danish Nitrate Policy in the 1980s, ed. Institute of Agricultural Economics, Copenhagen, Rapport nr. 59;Dubgaard,1991
2. Danish Policy Measures to Control Agricultural Impacts on the Environment. Institute of Agricultural Economics, Copenhagen, Rapport nr. 52;Dubgaard,1990
3. Denitrification in field soils
4. Book of Abstracts, Ghent,1994