A development of the Sturm - Liouville method for solving a boundary-value problem for the biharmonic equation. Neliniini Kolyvannya, [S. l.], v. 6, n. 3, p. 368–377, 2003. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/274. Acesso em: 22 jan. 2026.