Muhammad Tufail and  Jawad Hussain and  Hammad Hussain and  Imran Hafeez and  Naveed Ahmad,  Analysis of Rural Roads in Developing Countries Using Principal Component Analysis and Simple Average Technique in the Development of a Road Safety Performance Index.   journal   = {International Journal of Transport and Vehicle Engineering}, [online]. World Academy of Science, Engineering and Technology.
    February 2021, vol. 171(3). 120 - 127
    [viewed 05 May 2024]. Available from: https://publications.waset.org/pdf/10011889.