Abdul Rahman, R. ., M. A. . Zulkefle, S. H. . Herman, and R. I. . Alip. “Physical Properties of Different Thicknesses ZnO Thin Films Prepared via Sol-Gel Spin Coating Technique”. Scientific Research Journal, vol. 18, no. 2, Aug. 2021, pp. 147-60, doi:10.24191/srj.v18i2.13035.