Cheewaworanontree, Y., Thongsin, K., & Rontlaong, P. (2026). Study on the Optimal Factors for Briquetting Charcoal from Coconut Shells Using a Full Factorial Experimental Design. Wichcha Journal Nakhon Si Thammarat Rajabhat University, 45(1), 48–62. https://doi.org/10.65217/wichchajnstru.2026.v45i1.265278