1. E. Prichard, in: E.J. Newman (Editor), Quality in the Analytical Chemistry Laboratory, John Wiley and Sons, Chichester, 1995.
2. CEN, General Criteria for Operation of Testing Laboratories (European Standard 45001), CEN/CENELEC, Brussels, 1989.
3. ISO, Guidelines for Assessing the Technical Competence of Testing Laboratories, ISO Guide 25-1978 E, International Organization for Standardization, Geneva, 1978.
4. PerspectiveTraceability of Chemical Analysis
5. Traceability and comparability of "Amount of Substance" measurements: report of a joint CITAC EURACHEM workshop held at Noordwijkerhout, The Netherlands