Azhar Shiddiq, Muhammad, and Isti Pudjihastuti. “Making Silica Gel by Utilizing Candlenut and Palm Oil Shell Ash”. Eduvest - Journal of Universal Studies 1, no. 3 (March 15, 2021): 133–141. Accessed October 9, 2025. http://eduvest.greenvest.co.id/index.php/edv/article/view/24.