Synthesis of a one-part geopolymer system for soil stabilizer using fly ash and volcanic ashApril Anne S. Tigue, Jonathan R. Dungca, Hirofumi Hinode, Winarto Kurniawan and Michael Angelo B. PromentillaMATEC Web Conf., 156 (2018) 05017DOI: https://doi.org/10.1051/matecconf/201815605017