J. Arnold, Francisco, Marcos S. Gonçalves, Leonardo L. Bravo Roger, and Sérgio S. Mühlen. “Electric Impedance of Piezoelectric Ceramics under Acoustic Loads”. ECTI Transactions on Electrical Engineering, Electronics, and Communications 12, no. 2 (August 27, 2014): 48–54. accessed April 15, 2025. https://ph02.tci-thaijo.org/index.php/ECTI-EEC/article/view/170819.