N. P. Abiyoga, D. O. Dwina, O. Alfernando, and F. D. Putri, “Mechanical Properties Improvement of Peat Soils Stabilized by Palm Oil Fuel Ash (POFA) based Geopolymer”, j.ris.technol.pencegah., vol. 16, no. 2, pp. 176–185, Nov. 2025.