1. DIN EN ISO/IEC 17025 General requirements for the competence of calibration and testing laboratories (1999) ISO, Geneva
2. EU Water Framework Directive: Directive 2000/60/EC of the European Parliament and of the Council establishing a framework for the Community action in the field of water policy (2000) Amtsblatt: L 327
3. King B (1997) Metrologia 34:77–82
4. Labarraque G, Rivier C, Marschal A (1999) In: Proceedings of the 9th International Metrology Congress, Bordeaux, France, October 1999
5. Mutual Recognition Arrangement, Available at http://www.bipm.fr/en/convention/mra