Kristianingrum, S. et al. 2022. The Effectiveness of Active Carbon Adsorbent of Cassava Peel (Manihot Esculenta Cranzts) in Reduce Level of Chromium Metal in Tannery Liquid Waste. Indonesian Journal of Chemistry and Environment. 5, 2 (Dec. 2022), 58–67. DOI:https://doi.org/10.21831/ijoce.v5i2.18813.