1. Joint Working group 33∕23.12.: ‘Insulation co-ordination of GIS: return of experience, on site tests and diagnostic techniques’,CIGRE Electra, 1998,176, pp. 67–97
2. CIGRE WG 15.03: ‘Diagnostic methods for GIS insulating systems’. CIGRE paper, 15∕23-10, Paris, 1992
3. Working group 15.03.: ‘Partial discharge detection system for GIS: sensitivity verification for the UHF method and the acoustic method’,CIGRE Electra, 1999,183, pp. 75–87