Thi Hong, Tran. “MAKING THE COMPARISION OF BEARING CAPACITIES AND ECONOMICAL EFFECTED BY THE UNDER-REAMEAD OVER UNIFORM LARGE DIAMETER PILES”. Science and Technology Development Journal 3, no. 7&8 (August 31, 2000): 89-93. Accessed May 13, 2024. http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/3585.