“…The DC conductivity behaviour of a variety of chalcogenide glasses such as Ge,Sb,Se,, As,Se, (Mohan and Rao 1985), As-Te based glasses (Triberis 1986), phosphorushybrate and phosphotungstate glasses (Selvaraj and Rao 1988) and the DC conduction in RF sputtered S O , films (Meaudre el d 1983, Meaudre and Meaudre 1984, Triberis 1987, 1988a have been very satisfactorily analysed using Triberis and Friedman's model (1981) in which correlations are ignored.…”