S. Hyun Choi, C. Whan Oh, K. Ha Lee, Y. Boo Lee, E. Kyeong Choi, and S. Wook Kim, “A preliminary study on the new geotechnical weathering index in the evaluation of altered biotite granite”, IJET, vol. 7, no. 2.23, pp. 91–98, Apr. 2018, doi: 10.14419/ijet.v7i2.23.11891.