P., Pudjisuryadi, and Tavio . “Compressive Strength Prediction of Square Concrete Columns Retrofitted With External Steel Collars”. Civil Engineering Dimension 15, no. 1 (April 3, 2013): 18-24. Accessed April 26, 2024. https://ced.petra.ac.id/index.php/civ/article/view/18677.