Rungrodnimitchai, Supitcha, Wachira Phokhanusai, and Natthapong Sungkhaho. “Preparation of Silica Gel from Rice Husk Ash Using Microwave Heating”. Journal of Metals, Materials and Minerals 19, no. 2 (April 15, 2017). Accessed April 29, 2024. https://jmmm.material.chula.ac.th/index.php/jmmm/article/view/235.