Syahrulyati, Teti, et al. “Reserve Potential Sandy Clay As a Raw Materials Cement Village Hambalang, County Citeureup District BogorProvince Jawabarat –  Indonesia”. International Journal of Engineering and Technology, vol. 7, no. 3.30, May 2026, pp. 167-71, https://doi.org/10.14419/ijet.v7i3.30.19084.