M. Mahini, H. Moharrami, and G. Cocchetti, “A dissipated energy maximization approach to elastic-perfectly plastic analysis of planar frames”, Arch. Mech., vol. 65, no. 3, pp. 171–194, Jun. 2013, Accessed: Dec. 13, 2025. [Online]. Available: https://am.ippt.pan.pl/index.php/am/article/view/v65p171