1. IEC internet address:
http://www.iec.ch
2. DKE internet address:
http://www.dke.de
3. CIGRE internet address:
http://www.cigre.org
4. PTB internet address:
http://www.ptb.de
5. Schon, K., Lucas, W.: Worldwide interlaboratory test comparisons of high voltage impulse dividers. 2nd ERA conference on high voltage measurements and calibration, Arnhem, pp. 3.1.1–3.1.9 (1994)