Saran, M., and M. Kleiber. “A Note on the Perturbation Approach to Nonlinear Static Analysis of Elastic Plane Trusses”. Engineering Transactions 32, no. 3 (September 30, 1984): 315–327. Accessed June 10, 2025. https://et3.ippt.pan.pl/index.php/et/article/view/1899.