Enxiao Yuan and  Xiaomin Zhang,  Another Structure of Weakly Left C-wrpp Semigroups.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    February 2014, vol. 86(2). 423 - 426
    [viewed 20 September 2024]. Available from: https://publications.waset.org/pdf/9997826.