บุญภิละ น. (2019). Designing and developing of pearl decorative souvenir; Ban Nonglad, Thonnalab sub-district, Ban Dung District, Udon Thani province. Mahachula Academic Journal, 6(ฉบับพิเศษ), 51–65. Retrieved from https://so04.tci-thaijo.org/index.php/JMA/article/view/181005