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http://www.vtt.fi
/ket/citac/traceability
2. BIPM, IEC, IFCC, ISO, IUPAC, IUPAP, O1ML (1995) Guide to the Expression of the uncertainty in measurement. ISO, Geneva
3. Consultative Committee for Amount of Substance (Bureau International des Poids et Mesures)http://www.bipm.org/enu s/2_Commi ttees/CCQM. shtml
4. EURACHEM/CITAC Guide (2000) Qualifying uncertainty in analytical measurement, 2nd edn., Final Draft April 2000. EURACHEM
5. ISO/IEC 17025 (1999) General requirements for the competence of testing and calibration laboratories. ISO, Geneva