YU, J.G.; ZHANG, B.; LEFEBVRE, J.E.; ZHANG, CH. Wave propagation in functionally graded piezoelectric rods with rectangular cross-section. Archives of Mechanics, Warsaw, Poland, v. 67, n. 3, p. 213–231, 2015. DOI: 10.24423/aom.1692. Disponível em: http://am.ippt.gov.pl/index.php/am/article/view/v67p213. Acesso em: 17 jan. 2026.