BÉDA, Péter B. CRITICAL EIGENMODES AND INTRINSIC MATERIAL LENGTH Periodica Polytechnica Transportation Engineering, [S. l.], v. 26, n. 1-2, p. 61–70, 1998. Disponível em: https://pp.bme.hu/tr/article/view/6578. Acesso em: 4 may. 2024.