1. Department of Nanometrology, Wrocław University of Science and Technology, Janiszewskiego 11/17, 50-370 Wroclaw, Poland
2. Time and Length Department, Central Office of Measures, Elektoralna 2, 00-139 Warsaw, Poland
3. Electricity and Radiation Department, Central Office of Measures, Elektoralna 2, 00-139 Warsaw, Poland
4. Department of Physical Chemistry and Electrochemistry, Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Krakow, Poland