KALIS, H. The exact finite‐difference scheme for vector boundary‐value problems with piece‐wise constant coefficients. Mathematical Modelling and Analysis, [S. l.], v. 3, n. 1, p. 114–123, 1998. DOI: 10.3846/13926292.1998.9637094. Disponível em: https://journals.vilniustech.lt/index.php/MMA/article/view/9995. Acesso em: 2 jun. 2025.