WASET
    D.R Prince Williams,  Fuzzy Ideals in Near-subtraction Semigroups.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    July 2008, vol. 19(7). 458 - 465
    [viewed 19 April 2024]. Available from: https://publications.waset.org/pdf/14409.