Positron distributions and lifetimes in MxC60 (M : alkali or alkaline-earth) S. ISHIBASHI, N. TERADA, M. TOKUMOTO, N. KINOSHITA et H. IHARA J. Phys. IV France, 03 C4 (1993) C4-153-C4-159 DOI: 10.1051/jp4:1993421