1. ISO, 1993, Guide to the Expression of Uncertainty in Measurement.
2. Task specific uncertainty in coordinate metrology, Keynote paper;Wilhelm;Annals of CIRP,2001
3. An industrial comparison of coordinate measuring machines in Scandinavia with focus on uncertainty statements;Hansen;Precision Engineering,1999
4. Coordinate Measuring Machines in the Calibration Chain;Trapet;Bulletin du Bureau National de Mètrologie, Paris,1995
5. Trapet E. Franke M., Härtig, F. Schwenke H., Wäldele, F. Cox M. Forbes A. Delbressine F. Schellekens P. Trenk M. Meyer H. Moritz G. Guth, Th., Wanner, N., 1999, Traceability of Coordinate Measuring Machines According to the Method of the Virtual Measuring Technique, PTB-F-35, PTB, Braunschweig, ISBN 3-89701-330-4.