Positron annihilation : Proceedings of the 9th International Conference on Positron Annihilation, August 26-31, 1991, Szombathely, Hungary. Pt.3 pp.1459-1462, 1992. Aederlmannsdorf, Switzerland. Trans Tech Publications
Positron annihilation : Proceedings of the 9th International Conference on Positron Annihilation, August 26-31, 1991, Szombathely, Hungary. Pt.3 pp.1993-1996, 1992. Aederlmannsdorf, Switzerland. Trans Tech Publications