DIAB, Sulaiman Abo. The natural boundary conditions as a variational basis for finite element methods. Computer Assisted Methods in Engineering and Science, [S. l.], v. 8, n. 2-3, p. 213–226, 2023. Disponível em: https://cames3.ippt.pan.pl/index.php/cames/article/view/1165. Acesso em: 19 apr. 2025.