H. Sanecki and A. P. Zieliński, “The Trefftz finite elements modelling crack propagation”, CAMES, vol. 15, no. 3-4, pp. 353–368, Jul. 2022, Accessed: Apr. 19, 2025. [Online]. Available: https://cames3.ippt.pan.pl/index.php/cames/article/view/742