Sutrisno, Julia Dwi Ananda Putri, and Sumarwahyudi. “Natural Coloring Innovation: Analysis of Ecoprint Process on Leather at NURB Leather Gallery Malang ”. IJESS International Journal of Education and Social Science 6, no. 1 (April 15, 2025): 23–32. Accessed November 16, 2025. https://ejournal.aissrd.org/index.php/ijess/article/view/369.