9.Choi, H. Y., Choi, S. W., Lee, K. W., Hwang, H. Z, Kim, M. H., Kim, M. H., “An Experimental
Study on the Carbonation and Resistance to Surface Attack of Concrete with Hwangtoh
Admixture,” The Architectural Institute of Korea, Vol. 21, No. 1, 2001, pp. 353-356.