A MODEL FOR EXPLAINING THE MÖSSBAUER SPECTRA OF FERRIMAGNETIC SPINELS WITH A HIGH DEGREE OF DIAMAGNETIC SUBSTITUTION E. De Grave, A. Govaert, D. Chambaere et G. Robbrecht J. Phys. Colloques, 40 C2 (1979) C2-669-C2-670 DOI: 10.1051/jphyscol:19792232