Cappus, D., Xu, C., Ehrlich, D., Dillmann, B., Ventrice, C., Al Shamery, K., et al. (1993). Hydroxyl groups on oxide surfaces: NiO(100), NiO(111) and Cr2O3(111). Chemical Physics, 177(2), 533-546. doi:10.1016/0301-0104(93)80031-4.