PECULIARITIES OF THE SPIN STATE AND THE DISTRIBUTION OF Fe3+ IN SODIUM BORATE GLASSES V.K. Imshennik, I.P. Suzdalev, Yu.V. Maksimov et F.J. Litterst J. Phys. Colloques, 41 C1 (1980) C1-267-C1-268 DOI: 10.1051/jphyscol:1980192