SOFT AND HARD PIEZOELECTRIC MATERIALS FOR THE CONSTRUCTION OF A PIEZOELECTRIC SONOTRODE MOTOR. ELECTRICAL MACHINES, MATERIALS AND DRIVES — PRESENT AND TRENDS, [S. l.], v. 21, n. 1, p. 64–69, 2026. DOI: 10.36801/apme.2025.1.7. Disponível em: https://journal.iem.pub.ro/apme/article/view/1798. Acesso em: 1 jul. 2026.