Dennis L. Owuor and  Okuthe P. Kogeda and  Johnson I. Agbinya,  Three Tier Indoor Localization System for Digital Forensics.   journal   = {International Journal of Electronics and Communication Engineering}, [online]. World Academy of Science, Engineering and Technology.
    April 2017, vol. 126(6). 651 - 659
    [viewed 04 July 2020]. Available from: https://publications.waset.org/pdf/10007218.