Zhao, Wenyan, Wuyou Fu, Haibin Yang, Chuanjin Tian, Minghui Li, Juan Ding, Wei Zhang, Xiaoming Zhou, Hui Zhao, and Yixing Li. 2011. “Synthesis and Photocatalytic Activity of Fe-Doped TiO2 Supported on Hollow Glass Microbeads”. Nano-Micro Letters 3 (1):20-24. https://doi.org/10.1007/BF03353647.