WASET
    Imen Ammari and  Mourad Elloumi and  Ala Eddine Barouni,  Courses Pre-Required Visualization Using Force Directed Placement Technique.   journal   = {International Journal of Computer and Information Engineering}, [online]. World Academy of Science, Engineering and Technology.
    April 2013, vol. 76(4). 476 - 480
    [viewed 26 April 2024]. Available from: https://publications.waset.org/pdf/3227.