Abu Mansor, M. Luqman Harith, et al. “Deposition and Characterization of Cobalt Doped Titanium Dioxide Thin Films Using Sol-Gel Method”. Journal of Science and Technology, vol. 10, no. 2, Aug. 2018, https://penerbit.uthm.edu.my/ojs/index.php/JST/article/view/2957.