Arej K. Mahmod, Mohammed M. Salman, Lubna A. Al-Jabbar. “Investigating the Effect of Bacillus Subtilis Bacteria and Eggshell Powder on Some Properties of Concrete”. Design Engineering, no. 1 (March 24, 2022): 2606 - 2627. Accessed July 22, 2024. http://thedesignengineering.com/index.php/DE/article/view/9286.