Proficiency testing by interlaboratory comparisons - Part 2: Selection and use of proficiency testing schemes by laboratory accreditation bodies (ISO/IEC Guide 43-2:1997)
German standard methods for the examination of water, waste water and sludge - General information (group A) - Part 45: Interlaboratory comparisons for proficiency testing of laboratories (A 45)— 36 стр.
Air quality - Measurement of stationary source emissions - Application of EN ISO/IEC 17025:2005 to periodic measurements; German version CEN/TS 15675:2007— 44 стр.