Trong, Dang Xuan, Le Khanh Toan, Ha Thanh Ngoc, and Nguyen Tien Khiem. 2020. “Modal Analysis of Cracked Tower Crane With an Experimental Validation”. Vietnam Journal of Science and Technology 58 (6). Hanoi, VN:776-88. https://doi.org/10.15625/2525-2518/58/6/15298.