Belubekyan, Mels V., and Ararat A. Papyan. “VIBRATIONS OF PIEZOELECTRIC LAYER of CLASS 6mm WITH RIGIDLY CLAMPED AND FREE EDGES UNDER INITIAL CONDITIONСS”. Proceedings of the YSU A: Physical and Mathematical Sciences, vol. 54, no. 3 (253), Dec. 2020, pp. 146-52, doi:10.46991/PYSU:A/2020.54.3.146.