L. Tao and  T. J. Sun and  Z. H. Li,  Rough Set Based Intelligent Welding Quality Classification.   journal   = {International Journal of Chemical and Molecular Engineering}, [online]. World Academy of Science, Engineering and Technology.
    December 2011, vol. 60(12). 1128 - 1131
    [viewed 22 February 2020]. Available from: https://publications.waset.org/pdf/4729.