Pongphet, P., Onsalung, N., & Thinvongpituk, C. (2012). The Study on the Crush Characteristic of Polyurethane Foam-filled Rectangular Steel Tubes Under Compressive Load. Engineering and Applied Science Research, 37(2), 101–108. retrieved from https://ph01.tci-thaijo.org/index.php/easr/article/view/1695