Thongmak, Narumol, Sunwanee Jijai, Warunee Hajimasalaeh, Saina Muleng, and Porntip Sridang. “Efficiency of Palm Oil Mill Fly Ash for Residential Building Wastewater Treatment”. Rajamangala University of Technology Srivijaya Research Journal 13, no. 2 (July 27, 2021): 269–284. Accessed May 1, 2024. https://li01.tci-thaijo.org/index.php/rmutsvrj/article/view/240547.