Sivasubramanian, K., K. Ramanjaneyulu, K. Jaya, and M. Neelemegam. “Non-Destructive Evaluation in High Strength Concrete Using Ultrasonic Pulse Echo”. Journal of Structural Engineering, vol. 41, no. 4, Nov. 2024, pp. 341-8, http://14.139.176.44/index.php/JOSE/article/view/912.