1. ISO/IEC, ISO/IEC 17043: conformity assessment – general requirements for proficiency testing, ISO, Geneva, 2010.
2. ISO/IEC, ISO/IEC 17025: general requirements for the competence of testing and calibration laboratories, ISO, Geneva, 2005.
3. ISO/IEC, ISO/IEC 13528: statistical methods for use in proficiency testing by interlaboratory comparisons, ISO, Geneva, 2005.
4. B.I. des Poids et Mesures, BIPM key comparison database, (accessed at April 8th, 2015).
5. The evaluation of key comparison data;Cox;Metrologia,2002