1. A Benouis, N Khaldi and ML Benmalek,Uncertainties of strength concrete estimation by ultrasonic NDT (Admixture effects).(1999).
2. BS1881-202(1986), Recommendations for surface hardness testing by rebound hammer.
3. BS 1881-203 (1986), Recommendations for measurement of velocity of ultrasonic pulses in concrete, BSI, U.K.
4. De Almeida, 1991, I.R. Non-destructive Testing of High Strength Concretes: Rebound (Schmidt Hammer and Ultrasonic Pulse Velocity), Quality Control of Concrete Structures. L. Taerwe, H. Lambotte (Eds.), Proceedings of the International Symposium held by RILEM, Belgium, E&FN SPON, U.K., pp. 387± 397.
5. IS 13311 (Part II): 1992 Non-Destructive Testing of Concrete –Methods of test(Rebound Hammer).