Afisna, L. P., V. D. Verdia, M. Syaukani, and A. Saputra. “Adsorbent-Based Biogas Quality Analysis through Purification Process”. Jurnal Pendidikan Teknologi Kejuruan, vol. 5, no. 3, Aug. 2022, pp. 70-75, doi:10.24036/jptk.v5i3.27623.