5.Lee, W. S., Yun, H. D., Kim, S. W., Choi, K. S., You, Y. C., and Kim, K. H., “The
                           Effect of Replacement Ratio of Recycled Coarse Aggregate on Shear Strength of Reinforced
                           Concrete Beams without Shear Reinforcement,” Journal of the Architectural Institute
                           of Korea, Vol.23, No.10, 2007, pp. 3-10.
