Erina, Desty, and Agustinus Hariadi Djoko Purwanto. 2025. “Analysis of the Implementation of the ISO 9001:2015 Quality Management System Using GAP Analysis(Case Study at a National Gas Distribution Company)”. Business, Economics, Law, Communication, and Social Sciences 1 (5): 611-23. https://doi.org/10.000000/belacoss.v1i5.457.