Anurak, P., and N. Koohathongsumrit. “REDUCTION OF NONCONFORMING PRODUCTS IN PLASTIC-PACKAGING INDUSTRY USING 2k FACTORIAL EXPERIMENT DESIGN”. Research Journal Phranakhon Rajabhat : Science and Technology, vol. 21, no. 1, June 2026, pp. 69-82, https://li01.tci-thaijo.org/index.php/PRRJ_Scitech/article/view/271052.