Cederbaum, G., and G. Suire. “Parametric Instability of Viscoelastic Nonlinear (Elastica) Columns”. Engineering Transactions 44, no. 2 (July 31, 1996): 157–167. Accessed June 12, 2025. https://et3.ippt.pan.pl/index.php/et/article/view/1456.