INVESTIGATION OF THE METAL-TO-SEMIMETAL TRANSITION IN NiS BY 61Ni-MÖSSBAUER SPECTROSCOPY J. FINK, G. CZJZEK, H. SCHMIDT, K. RUEBENBAUER, J.M.D. COEY et R. BRUSETTI J. Phys. Colloques, 35 C6 (1974) C6-675-C6-677 DOI: 10.1051/jphyscol:19746148