2Herrera F, Herrera-Viedma E, Verdegay J L. A model of consensus in group decision making under linguistic assessments [J~. Fuzzy Sets and Systems, 1996 (78) : 73- 87.
3Naeni L M, Salehipour A. Evaluating fuzzy earned value indices and estimates by applying alpha cuts [ J ]. Expert systems with Applications, 2011 (38) : 8 193-8 198.
4Adamo J M. Fuzzy decision trees [ J ]. Fuzzy Sets and Systems, 1980 (4): 207-219.