1. Codex alimantarius austriacus,1980
2. An analytical check sample scheme: structure and guidelines for participants (1997–1998);AQUACHECK,1997
3. Technical reglementation concerning drinking water;Decision of the Flemish and Walloon Executive;Council Directive 89-990,1989
4. Relating to the quality of water intended for human consumption;European Commission;Council Directive 80/778 EEC,1980