THE EFFECT OF NON-METALLIC INCLUSIONS AND FILMS ON THE CATHODE ON SOME PROCESSES DURING VACUUM DISCHARGES D.I. Proskourovsky et V.F. Puchkarev J. Phys. Colloques, 40 C7 (1979) C7-411-C7-412 DOI: 10.1051/jphyscol:19797201