M. Abdul Rahim, S. Shahidan, C. O. Lee, N. A. A. Saiful Bahari, N. Abd Rahman, and A. Ayob, “The Behavior of Non-Destructive Test for Different Grade of Concrete”, IJIE, vol. 12, no. 9, pp. 1–8, Dec. 2020, Accessed: Apr. 07, 2026. [Online]. Available: https://publisher.uthm.edu.my/ojs/index.php/ijie/article/view/5336