WASET
    I. M. Yusuff and  O. M. Oni and  A. A. Aremu,  Computational Model for Prediction of Soil-Gas Radon-222 Concentration in Soil-Depths and Soil Grain Size Particles.   journal   = {International Journal of Chemical and Molecular Engineering}, [online]. World Academy of Science, Engineering and Technology.
    April 2020, vol. 161(5). 149 - 152
    [viewed 20 April 2024]. Available from: https://publications.waset.org/pdf/10011226.