1. L.A. Zadeh, Fuzzy sets. Inf. Control 8, 338–353 (1965)
2. K.T. Atanassov, Intuitionistic fuzzy sets, VII ITKR Session, Sofia, 20–23 June 1983 (Deposed in Centr. Sci.-Techn. Library of the Bulg. Acad. of Sci., 1697/84) (in Bulgarian), Reprinted: Int. J. Bioautomation 20(S1) (2016)
3. K.T. Atanassov, Intuitionistic fuzzy sets. Fuzzy Sets Syst. 20(1), 87–96 (1986)
4. G. Çuvalcıoğlu, S. Yılmaz, Some properties of OTMOs on IFSs. Adv. Stud. Contemp. Math. 20(4), 621–628 (2010)
5. G. Çuvalcıoğlu, E. Aykut, An application of the intuitionistic fuzzy modal operator Eα,β. NIFS 20(5), 57–61 (2014)