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2. Council Directive 91/676/EEC of 12 December 1991 concerning the protection of waters against pollution caused by nitrates from agricultural sources. European Commission (EC);Off. J. L,1991
3. Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora. European Commission (EC);Off. J. L,1992
4. Council Directive 98/83/EC of 3 November 1998 on the quality of water intended for human consumption. European Commission (EC);Off. J. L,1998