Meng, Za-Da, et al. “Heterogeneous Photocatalytic Degradation of Anionic and Cationic Dyes Over Fe-Fullerene TiO2 Under Visible Light”. Asian Journal of Chemistry, vol. 25, no. 11, June 2013, pp. 6001-7, doi:10.14233/ajchem.2013.14228.