Jian Tang, Characterizations of Ordered Semigroups by (∈,∈ ∨q)-Fuzzy Ideals. journal = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology. August 2012, vol. 68(8). 825 - 837 [viewed 20 September 2024]. Available from: https://publications.waset.org/pdf/13217.