Purbasari, A., T. W. Samadhi, dan Y. Bindar. Sulfuric Acid Resistance of Geopolymer Mortars from Co-Combustion Residuals of Bamboo and Kaolin. Vol. 18, no. 2, Desember 2018, hlm. 22-30, https://jurnal.ugm.ac.id/v3/AJChE/article/view/9021.