Wahyuni, Dwi, et al. “Reinforcement Of Soft Soil Using Soil Column Method (Soft Soil + CCR + RHA)”. Sriwijaya Journal of Environment, vol. 5, no. 3, Jan. 2021, pp. 172-7, https://ojs.pps.unsri.ac.id/index.php/ppsunsri/article/view/253.