Indrastika, Erwin Riski, et al. “Characterization of Activated Carbon from Mangosteen Peel (Garcinia Mangostana L.) Activated With Phosphoric Acid (H3PO4)”. Hydrogen: Jurnal Kependidikan Kimia, vol. 13, no. 1, Feb. 2025, pp. 58-64, doi:10.33394/hjkk.v13i1.14557.