Off-Centering of Pb and Sn Impurities in GeTe Induced by Strong Local Stress A.I. Lebedev, I.A. Sluchinskaya, V.N. Demin et I.H. Munro J. Phys. IV France, 7 C2 (1997) C2-1159-C2-1160 DOI: 10.1051/jp4:19972172