Singharat, K., S. Sangkarak, O. Pongsuk, and S. Junyapoon*. “Biogas Production from Bakery Wastewater in Two-Stage Anaerobic Digestion System”. CURRENT APPLIED SCIENCE AND TECHNOLOGY, vol. 17, no. 1, Jan. 2018, pp. 103-12, https://li01.tci-thaijo.org/index.php/cast/article/view/129465.