CHOI, Cheok; NAKAMURA, Gen; SHIROTA, Kenji. Variational approach for identifying a coefficient of the wave equation. CUBO, A Mathematical Journal, [S. l.], v. 9, n. 2, p. 81–101, 2007. Disponível em: https://cubo.ufro.cl/index.php/cubo/article/view/1593. Acesso em: 9 jan. 2026.