IMPURITIES AND THERMOLUMINESCENCETitanium-related defects in Lif : Mg, Ti T.G. Stœbe, J.B. Wolfenstine and W.C. Las J. Phys. Colloques, 41 C6 (1980) C6-265-C6-268 DOI: 10.1051/jphyscol:1980667