Sinthusarn, Apaporn, Somphon Sincharoenpokai, and Kartoon Pengprom. “An innovative of the portable electric tjanting pen”. Bulletin of Applied Sciences 15, no. 1 (June 30, 2026): 10–15. accessed September 2, 2026. https://ph03.tci-thaijo.org/index.php/BAS/article/view/3714.