Philaphan, P. J., and A. P. D. P. Pusing. “Solar Cells : Change to Energy”. Journal of Research and Development Institute Rajabhat Maha Sarakham University, vol. 6, no. 2, Dec. 2019, pp. 525-36, https://so03.tci-thaijo.org/index.php/rdirmu/article/view/233267.