Widarto, R., L. B. Suparma, and S. Siswosukarto. “Base Course Stabilization Performance Using Fly Ash-Based Geopolymers and Their Effect on Water Quality Standards”. UKaRsT, vol. 7, no. 1, Apr. 2023, pp. 1-16, doi:10.30737/ukarst.v7i2.4235.