Sumnieng Ongsupankul. (2006) Effectiveness of confining reinforcement on strength and ductility of reinforced concrete highway bridge piers /. Kasetsart University,:ม.ป.ท.Sumnieng Ongsupankul. 2006. Effectiveness of confining reinforcement on strength and ductility of reinforced concrete highway bridge piers /. ม.ป.ท.:Kasetsart University,;Sumnieng Ongsupankul. Effectiveness of confining reinforcement on strength and ductility of reinforced concrete highway bridge piers /. ม.ป.ท.:Kasetsart University, 2006. Print.