WASET
    Amoljit S. Gill and  Sanjeev Kumar,  Surface Roughness Evaluation for EDM of En31 with Cu-Cr-Ni Powder Metallurgy Tool .   journal   = {International Journal of Industrial and Manufacturing Engineering}, [online]. World Academy of Science, Engineering and Technology.
    July 2014, vol. 91(7). 1308 - 1313
    [viewed 25 April 2024]. Available from: https://publications.waset.org/pdf/9999010.