1. De invloed van bodemeigenschappen en bemesting op de opbrengst van mais en de emissies van ammoniak en nitraat. Rep. No. 131;Aarts,1990
2. Phosphorus (P) management in the ‘De Marke’ dairy farming system;Aarts;Nutr. Cycl. Agroecosyst.,2000
3. Directive of the Council of December 12, 1991 Concerning the Protection of Waters Against Pollution Caused by Nitrates from Agricultural Sources (91/676/EEC);Anonymous,1991
4. Mestkrant 2001;Anonymous,2001
5. An environmental–economic model at farm level to analyse institutional and technical change in dairy farming;Berentsen;Agric. Syst.,1995