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2. The use of reverse osmosis for removal of nitrate in drinking water;Bilidt,1985
3. Ground water quality—manuring; problems with nitrate in Eastern Gelderland;Bruyn;H2O,1984
4. Les nitrates dans l'eau potable—Différentes possibilités de traitement—Résultats obtenus par échanges d'ions;Deguin;J. fr. Hyd.,1978
5. Council directive of 15 July 1980 relating to the quality of water intended for human consumption, 80/778/EEC Off;European Community;J. Eur. Commun.,1980