Epitaxial growth and magnetic and electric properties of Co-doped TiO2 thin films - Is nonequilibrium doping an essential for ferromagnetism?J. Li, C. H. Sow, X. S. Rao, C. K. Ong and D. N. ZhengEur. Phys. J. B, 32 4 (2003) 471-476DOI: https://doi.org/10.1140/epjb/e2003-00128-1