Z. Murcinkova, V. Kompis, and M. Stiavnicky, “Trefftz functions for 3D stress concentration problems”, Comp. Assist. Methods Eng. Sci., vol. 15, no. 3-4, pp. 305–318, Jul. 2022, Accessed: Jun. 30, 2025. [Online]. Available: https://cames.ippt.pan.pl/index.php/cames/article/view/738