“Local Material Samboja Sand in East Kalimantan: Utilization With Fiber Reinforced Polymer Jacketing As an Effort to Increase the Concrete Strength”. JTT (Jurnal Teknologi Terpadu) 3, no. 2 (October 12, 2015). Accessed June 8, 2026. http://jurnal.poltekba.ac.id/index.php/jtt/article/view/90.