On the applicability of the rigid band model to the metallic sodium tungsten bronzes: A photoemission study using synchrotron radiationG. HollingerF.J. Himpselet al.1982Solid State Communications
Charge transfer in amorphous colored WO3 films observed by X-Ray photoelectron spectroscopyG. HollingerTran Minh Ducet al.1976Physical Review Letters