Structural, optical and electrical properties of undoped and indium doped zinc oxide prepared by spray pyrolysis M. Addou, A. Moumin, El idrissi B., M. Regragui, A. Bougrine, A. Kachouane and C. Monty J. Chim. Phys., 96 2 (1999) 232-244 DOI: 10.1051/jcp:1999133