L. Radziszewski, “The influence of the surface load exerted by a piezoelectric contact sensor on testing results: I. The displacement field in the solid”, Arch. Acoust., vol. 28, no. 2, Jan. 2003, Accessed: Jun. 15, 2025. [Online]. Available: https://acoustics.ippt.pan.pl/index.php/aa/article/view/446