IONIZATION AVERAGE FREQUENCY IN ANODE SHEATH OF PENNING-TYPE HIGH-VOLTAGE DISCHARGE N. A. Kervalishvili et V. P. KortkhonjiaJ. Phys. Colloques, 40 C7 (1979) C7-111-C7-112DOI: https://doi.org/10.1051/jphyscol:1979755