Mukti Hamjah Harahap และ Aulia E. Putri. (2020) Effect of variations in the composition and size of red sand grains on the quality of K-225 concrete. <i>Journal of Metals, Materials and Minerals</i>, <i>30</i>(4), 79-83.Mukti Hamjah Harahap และ Aulia E. Putri. "Effect of variations in the composition and size of red sand grains on the quality of K-225 concrete". Journal of Metals, Materials and Minerals 30 (2020):79-83.Mukti Hamjah Harahap และ Aulia E. Putri. Effect of variations in the composition and size of red sand grains on the quality of K-225 concrete. Metallurgy and Materials Science Research Institute Chulalongkorn University:ม.ป.ท. 2020.