Janaka J. Kumara, Yoshiaki Kikuchi, Takashi Kurashina, and Taichi Hyodo. “BASE RESISTANCE OF OPEN-ENDED PILES EVALUATED BY VARIOUS DESIGN METHODS”. GEOMATE Journal, vol. 11, no. 26, Oct. 2019, pp. 2643-50, https://geomatejournal.com/geomate/article/view/2658.