M. Sami Abdali, A. Shaker Hussein, and M. Hadi Shinen, “Study the Effect of Thickness on Optical Properties of Titanium Dioxide (TiO2) That Preparation of Via the Sol-Gel Process”, JK-Physics, vol. 12, no. 01, pp. 73–78, Jun. 2020, doi: 10.31257/2018/JKP/2020/120111.