MÖSSBAUER SPECTROSCOPIC STUDY OF SOME COMPLEX (M2O-MO-M2O3-SiO2 GLASSES E. de Grave, P. van Iseghem, R. de Batist and D. Chambaere J. Phys. Colloques, 41 C1 (1980) C1-269-C1-270 DOI: 10.1051/jphyscol:1980193