A. Grzyb, “On Dynamic Properties of Two Models of Beam on Nonlinear Foundation Subjected to Moving Load”, Eng. Trans., vol. 41, no. 3-4, pp. 337–350, Dec. 1993, Accessed: Jun. 09, 2025. [Online]. Available: https://et3.ippt.pan.pl/index.php/et/article/view/1573