OSCILLATORY INTERNAL FRICTION ASSOCIATED WITH DISLOCATION CORE REARRANGEMENT OF IMPURITY INTERSTITIALS IN ZIRCONIUM I.G. Ritchie et K.W. Sprungmann J. Phys. Colloques, 44 C9 (1983) C9-613-C9-617 DOI: 10.1051/jphyscol:1983992