Luang, Etwar, Joni Hermanto, and Muhammad Usamah. “Concrete Quality Design F’C 21 MPa Using SNI 7656:2012 Method Using Local Materials (C Ibu Selatan Quarry)”. JURNAL BIOSAINSTEK 8, no. 2 (July 4, 2026): 97–104. Accessed July 9, 2026. https://journal.tyarlyta.com/index.php/biosaintek/article/view/2789.