Sainudin, Muhammad Shabery. “Properties of Concrete Containing Mussel (Perna Viridis) Shell Ash As Partial Cement Replacement”. International Journal of Integrated Engineering, vol. 11, no. 9, Dec. 2019, pp. 154-63, https://publisher.uthm.edu.my/ojs/index.php/ijie/article/view/5441.