M. Zelinkova and  M. Ondova,  Effect of Fly Ash Fineness on Sorption Properties of Geopolymers Based On Liquid Glass.   journal   = {International Journal of Civil and Environmental Engineering}, [online]. World Academy of Science, Engineering and Technology.
    May 2015, vol. 101(5). 583 - 587
    [viewed 19 October 2019]. Available from: https://publications.waset.org/pdf/10001338.