Z. Turek, “Application of the Fourier cosine series to the approximation of solutions to initial non-Dirichlet boundary-value problems”, Arch. Mech., vol. 49, no. 4, pp. 635–645, Aug. 1997, Accessed: Mar. 12, 2026. [Online]. Available: https://am.ippt.pan.pl/index.php/am/article/view/v49p635