RF impedance measurements of DC atmospheric micro-discharges L. J. Overzet, D. Jung, M. A. Mandra, M. Goeckner, T. Dufour, R. Dussart and P. Lefaucheux Eur. Phys. J. D, 60 3 (2010) 449-454 Published online: 20 October 2010 DOI: 10.1140/epjd/e2010-00274-5