“UTILIZATION OF AROMATIC SULPHONES IN THE UPPER SHOES LEATHER TANNING PROCESS”. Berkala Penelitian Teknologi Kulit, Sepatu, dan Produk Kulit 22, no. 2 (December 16, 2024): 52–59. Accessed August 31, 2025. http://e-jurnal.atk.ac.id/new-jurnal/index.php/bptkspk/article/view/18.