Positron annihilation : Proceedings of the 9th International Conference on Positron Annihilation, August 26-31, 1991, Szombathely, Hungary. Pt.3 pp.1423-1426, 1992. Aederlmannsdorf, Switzerland. Trans Tech Publications
Proceedings of the 18th International Conference on Defects in Semiconductors : ICDS-18, Sendai, Japan, July 23-28, 1995. pp.1109-1116, 1995. Zurich, Switzerland. Trans Tech Publications
Shallow Impurities in Semiconductors : Proceedings of the Fifth International Conference on Shallow Impurities in Semiconductors "Physics and Control of Impurities", International Conference Center Kobe, Japan, 5 to 8 August, 1992. pp.483-487, 1993. Aedermannsdorf, Switzerland. Trans Tech Publications