Defect-induced magnetism in undoped wide band gap oxides: Zinc vacancies in ZnO as an example oleh G. Z. Xing, Y. H. Lu, Y. F. Tian, J. B. Yi, C. C. Lim, Y. F. Li, G. P. Li, D. D. Wang, B. Yao, J. Ding, Y. P. Feng, T. Wu