1. European Commission. 1991 Urban waste water treatment. Directive 91/271/EEC. European Commission Brussels Belgium.
2. European Commission. 1991 Nitrates. Directive 91/676/EEC. European Commission Brussels Belgium.
3. European Commission. 2000 Water framework. Directive 2000/60/EC. European Commission Brussels Belgium.
4. European Commission. 2002 Common fisheries policy. EC No 2371/2002. European Commission Brussels Belgium.
5. European Commission. 1992 Habitats. Directive 92/43/EEC. European Commission Brussels Belgium.