Kitthawee, U. “THE UPGRADE OF GRILLED SWINE COST FOR SUSTAINABLE DEVELOPMENT IN SAMPHRAN DISTRICT, NAKHON PATHOM PROVINCE”. Journal of Graduate School Sakon Nakhon Rajabhat University, vol. 13, no. 61, June 2016, pp. 165-72, https://so02.tci-thaijo.org/index.php/SNGSJ/article/view/59258.