Jiri Brozovsky, Calcium Silicate Bricks – Ultrasonic Pulse Method: Effects of Natural Frequency of Transducers on Measurement Results. journal = {International Journal of Architectural and Environmental Engineering}, [online]. World Academy of Science, Engineering and Technology. September 2014, vol. 93(9). 971 - 974 [viewed 25 April 2024]. Available from: https://publications.waset.org/pdf/9999379.