Riyanti, Anggrika, Hadrah Hadrah, and Arisanti Monica Zeusica Sihombing. “Recycling of Water Treatment Plant Sludge for Copper Adsorption from Aqueous Solutions”. Jurnal Lahan Suboptimal : Journal of Suboptimal Lands 13, no. 2 (October 1, 2024): 174–185. Accessed December 21, 2024. https://jlsuboptimal.unsri.ac.id/index.php/jlso/article/view/681.