1. (1) Intergovernmental Panel on Climate Change (IPCC): Radiative Forcing of Climate Change, p. 172 (1994)
2. (3) J. Alter, M. Ammann, W. Boeck, W. Degen, A. Diessner, H. Koch, F. Renaud, and S. Poehler: “N2/SF6 Gas-Insulated Line of a New GIL Generation in Service”, CIGRE Session 2002, No. 21-204 (2002)
3. (4) H. Goshima, H. Shinkai, and M. Yashima: “Lightning Impulse Breakdown Characteristics of High-pressure Nitrogen Gas under Quasi-Uniform Field Gap”, Proc. of 10th ACED, No. A-108, pp. 67-70, Kyoto (2000)
4. (5) H. Goshima, H. Shinkai, and M. Yashima: “Lightning Impulse Breakdown Characteristics of High-Pressure N2 under Non-Uniform Electric Field Gap in the Presence of a Metallic Particle”, Proc. of 12th International Symposium on High Voltage Engineering, No. 4-26, Bangalore (2001)