Ramadhania, Firanti. “Strengthening Vocational Competencies and Quality Culture in Small-Scale Food Enterprises: A Case Study of Tofu Production Improvement Using the Six Sigma Approach”. Journal of Supply Chain and Entrepreneurship 1, no. 3 (December 26, 2025): 111–120. Accessed January 16, 2026. https://www.ejournal.spdfharmony.com/index.php/josce/article/view/69.