Hanifah, Sarina, et al. “Column Study and Desorption Performance of Coffee Biomass-Calcium-Alginate Beads to Remove Pb²⁺ Ions from Aqueous Solutions ”. Jurnal Riset Sains Dan Kimia Terapan, vol. 11, no. 1, June 2025, pp. 1-10, doi:10.21009/JRSKT.111.01.