Mahmud Abba Tahir ,  Comparative Sulphate Resistance of Pozzolanic Cement Mortars.   journal   = {International Journal of Structural and Construction Engineering}, [online]. World Academy of Science, Engineering and Technology.
    June 2017, vol. 126(6). 773 - 776
    [viewed 24 April 2024]. Available from: https://publications.waset.org/pdf/10007313.