On covering generalized rough set: Covering rough membership function. - Qiu Jin; Lingqiang Li; Shoubin Sun (FSKD, 2012)

On the relationship between (diagonal) filters and (diagonal) stratified lattice-valued filters. - Lingqiang Li; Qiu Jin; Shoubin Sun (FSKD, 2012)

On fuzzifying matroids: Dual matroids and spanning. - Shoubin Sun; Zhenyu Xiu; Lingqiang Li (J. Intell. Fuzzy Syst., 2015)