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Guidelines for third-party certification and accreditation Guide 43 - Proficiency testing by interlaboratory comparisons, Part 1: Development and operation of proficiency testing schemes
Guidelines for third-party certification and accreditation - Guide 43 - Proficiency testing by interlaboratory comparisons, Part 2: Selection and use of proficiency testing schemes by laboratory accreditation bodies
Guideline for third-party certification and accreditation, Part 58: Calibration and testing laboratory accreditation systems - General requirements for operation and recognition
