Salas, A., Torres, J., Mejía de Gutiérrez, R. and Delvasto, S. 2013. Engineering properties of blended concrete with Colombian rice husk ash and metakaolin. Ingeniería y Competitividad. 15, 2 (Dec. 2013). DOI:https://doi.org/10.25100/iyc.v15i2.2609.