MÖSSBAUER EFFECT : A TEST FOR CHECKING THE NÉEL MODEL IN FERRIMAGNETIC RARE-EARTH IRON COMPOUNDS D. BARB, E. BURZO et M. MORARIU J. Phys. Colloques, 35 C6 (1974) C6-625-C6-627 DOI: 10.1051/jphyscol:19746136