M. Mahboubkhah and  H. Fayazfar,  Determination of Measurement Uncertainty in Extracting of Forming Limit Diagrams.   journal   = {International Journal of Industrial and Manufacturing Engineering}, [online]. World Academy of Science, Engineering and Technology.
    April 2009, vol. 28(4). 438 - 441
    [viewed 14 October 2019]. Available from: https://publications.waset.org/pdf/14390.