INFLUENCE OF THE STATE OF AGGREGATION OF DIVALENT CATION IMPURITIES ON THE F-COLORING KINETICS OF NaCl J.L. PASCUAL, F.J. LÓPEZ, F. JAQUE et F. AGULLÓ-LÓPEZ J. Phys. Colloques, 37 C7 (1976) C7-87-C7-88 DOI: 10.1051/jphyscol:1976712