1. Carleton, H. R. and Muratore J. F., “Ultrasonic Evaluation of Concrete,” Proceedings of the 1986 IEEE Ultrasonic Symposium, pp. 1017-1020.
2. ASCE, “Report Card for America's Infrastructure,” American Society of Civil Engineers, March 2001
3. Whitehurst, E.A., “Use of the Soniscope for Measuring Setting Time of Concrete,” Proceedings, ASTM, Vol.51, 1951, pp. 1166-1176.
4. “How Soon is soon Enough?”;Mather;ACI Journal,1976
5. Popovics, S., Silva-Rodrigez, R., Popovics, J.S., “Behavior of Ultrasonic Pulses in Fresh Concrete”, New Experimental Techniques for Evaluating Concrete Material and Structure Performance, ACI Publication SP143, 1994, pp.207-225.