Pratama, Angga, and Selfina Gala. “Comparative Evaluation of Aqua Regia and Tri-Acid Digestion Methods for the Determination of As, Cu, and Pb in an Ore-Grade Certified Reference Material by Flame Atomic Absorption Spectrometry”. Journal of Green Chemical and Environmental Engineering, vol. 2, no. 2, July 2026, pp. 122-3, https://doi.org/10.63288/jgcee.v2i2.28.