VANADATE SEMICONDUCTING GLASSES DOPED WITH OXIDES OF OTHER TRANSITION METALS L.D. Bogomolova, V.A. Jachkin, M.P. Glassova and S.N. Spasibkina J. Phys. Colloques, 42 C4 (1981) C4-993-C4-996 DOI: 10.1051/jphyscol:19814216