WASET
    Awais Ahmad Khan and  Emad Abouel Nasr and  H. M. A. Hussein and  Abdulrahman Al-Ahmari,  An Automatic Feature Extraction Technique for 2D Punch Shapes.   journal   = {International Journal of Information and Communication Engineering}, [online]. World Academy of Science, Engineering and Technology.
    March 2016, vol. 113(5). 884 - 888
    [viewed 19 April 2024]. Available from: https://publications.waset.org/pdf/10004369.