Nakrachata-amon, T., and S. Pathumnakul. “Optimizing the pork supply chain: A model integrating feed production and pig farming with outsourcing and subcontracting costs”. Engineering and Applied Science Research, vol. 52, no. 4, June 2025, pp. 375-83, https://ph01.tci-thaijo.org/index.php/easr/article/view/260734.