On Simplified Axiomatic Characterizations of (υ σ)-Fuzzy Rough Approximation Operators. - Hongying Zhang; Haijuan Song (Int. J. Uncertain. Fuzziness Knowl. Based Syst., 2017)

Feature selection based on generalized variable-precision (( vartheta , sigma ) ) -fuzzy granular rough set model over two universes. - Hong-Ying Zhang; Haijuan Song; Shuyun Yang (Int. J. Mach. Learn. Cybern., 2019)