Hardiyanto, Agung, and Erma Suryani. “The Development of Customer Self-Service Prototype for Readymix Concrete After Sales Service Using Design Thinking Method”. Jurnal Indonesia Sosial Teknologi 5, no. 12 (December 30, 2024): 6192–6205. Accessed January 9, 2025. https://jist.publikasiindonesia.id/index.php/jist/article/view/8859.