Hayashi, Yoshinori, Koji Masuda, and Shigeyuki Haruyama. “A Framework That Shows the Process to Help Customers Understand the Value at Each Stage of Product Development”. International Journal of Integrated Engineering 16, no. 2 (May 30, 2024): 212–217. Accessed June 30, 2024. https://penerbit.uthm.edu.my/ojs/index.php/ijie/article/view/16231.