Electron excitation of neutral and ionic levels in Townsend discharges of argon at high E/NG. N. Malović, J. V. Božin, B. M. Jelenković and Z. Lj. PetrovićEur. Phys. J. D, 7 1 (1999) 129-135DOI: https://doi.org/10.1007/s100530050357