Tumengkol, Herman Alfis, et al. “Optimizing Concrete Durability in Aggressive Environments Using Silica-Rich Tropical Hardwood Ash As a Supplementary Cementitious Material (SCM)”. Engineering, Technology & Applied Science Research, vol. 15, no. 6, Dec. 2025, pp. 29090-6, doi:10.48084/etasr.13670.