EXAFS AND RAMAN-STUDY OF STOICHIOMETRIC AND OXIDIZED ND2NIO4+DELTA - PRIETO, C; DEANDRES, A; MEDARDE, M; MARTINEZ, JL; FERNANDEZDIAZ, MT; RODRIGUEZCARVAJAL, J; SAEZPUCHE, R; FERNANDEZ, F; (Solid State Communications, 1991)