W. Wai-Chi, A. Azid, and B. Majlis, “Formulation of stiffness constant and effective mass for a folded beam”, Arch. Mech., vol. 62, no. 5, pp. 405–418, Nov. 2010, Accessed: Jan. 17, 2026. [Online]. Available: http://am.ippt.gov.pl/index.php/am/article/view/v62p405