Ikhsan, J., S. Sulastri, and E. Priyambodo. “The Modification of Silica Surfaceseparated from Overflowing Mud in Lapindo Indonesia as Cation Exchange Adsorbent”. YRU Journal of Science and Technology 2, no. 2 (May 20, 2018): 1–7. accessed September 21, 2026. https://li01.tci-thaijo.org/index.php/yru_jst/article/view/124546.