Xiaowei Wei Bin Pang 0004 Ju-Sheng Mi Axiomatic characterizations of <i>L</i>-fuzzy rough sets by <i>L</i>-fuzzy unions and <i>L</i>-fuzzy intersections. 277-312 2022 51 Int. J. Gen. Syst. 3 https://doi.org/10.1080/03081079.2021.2024178 db/journals/ijgs/ijgs51.html#WeiPM22