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Williams, J M; Porter, C H; Lyons, W* (1999) Power supplies and measurement techniques for the calibration of high current DC shunts. In: BEMC 99 - 9th International Conference on Electromagnetic Measurement, 2-4 November 1999, Brighton, UK.

Williams, J M; Hartland, A; Dupuy, N B; Porter, C H (1993) Improvements in the traceability of resistance measurements at NPL. In: 6th British Electromagnetic Measurements Conference Digest (BEMC 93), 2-4 November 1993, NPL, Teddington, UK.