References
- R. Biswas, Rosenfeld's fuzzy subgroups with interval-valued membership functions, Fuzzy set and systems, 63 (1995), 87-90.
- M. Cheong and K. Hur, Interval-valued fuzzy ideals and bi-ideals of a semigroup, IJFIS, 11 (2011), 259-266. https://doi.org/10.5391/IJFIS.2011.11.4.259
- J. Y. Choi, S. R. Kim and K. Hur, Interval-valued smooth topological spaces, Honam Math.J., 32(4) (2010), 711-738. https://doi.org/10.5831/HMJ.2010.32.4.711
- M.B.Gorzalczany, A method of inference in approximate reasoning based on interval-values fuzzy sets, Fuzzy sets and Systems, 21 (1987), 1-17. https://doi.org/10.1016/0165-0114(87)90148-5
- S. Y. Jang, K. Hur and P. K. Lim, Interval-valued fuzzy normal subgroups, IJFIS, 12(3) (2012), 205-214. https://doi.org/10.5391/IJFIS.2012.12.3.205
- J. M. Howie, An Introduction to Semigroup Theory, Academic Press, New York, 1976.
- K.Hur, J. G. Lee and J. Y. Choi, Interval-valued fuzzy relations, JKIIS, 19(3) (2009), 425-432. https://doi.org/10.5391/JKIIS.2009.19.3.425
- H. Kang, Interval-valued fuzzy subgroups and homomorphisms, Honam Math.J., 33(4) (2011), 499-518. https://doi.org/10.5831/HMJ.2011.33.4.499
- H. Kang and K.Hur, Interval-valued fuzzy subgroups and rings, Honam Math.J., 32(4) (2010), 593-617. https://doi.org/10.5831/HMJ.2010.32.4.593
- K. C. Lee, H. Kang and K.Hur, Interval-valued fuzzy generalized bi-ideals of a semigroup, Honam Math.J., 33(4) (2011), 603-611. https://doi.org/10.5831/HMJ.2011.33.4.603
- J. G. Lee, K. Hur and P. K. Lim, Interval-valued fuzzy congruences on a semigroup, IJFIS, 13(3) (2013), 231-244. https://doi.org/10.5391/IJFIS.2013.13.3.231
- T.K.Mondal and S.K.Samanta, Topology of interval-valued fuzzy sets, Indian J. Pure Appl. Math., 30(1) (1999), 20-38.
- M. K. Roy and R. Biswas, I-v fuzzy relations and Sanchez's approach for medical diagnosis, Fuzzy set and systems, 47 (1992), 35-38. https://doi.org/10.1016/0165-0114(92)90057-B
- L.A.Zadeh, Fuzzy sets, Inform and Control, 8 (1965), 338-353. https://doi.org/10.1016/S0019-9958(65)90241-X
- L.A.Zadeh, The concept of a linguistic variable and its application to approximate reasoning-I, Inform. Sci, 8 (1975), 199-249. https://doi.org/10.1016/0020-0255(75)90036-5
- C.Zhang, Group congruences on a regular semigroup, J.Shandong Univ., 4 (1995), 376-384.
- L.A.Zadeh, Fuzzy complete inner-unitary subsemigroups and fuzzy group congruences on a regular semigroup, Fuzzy Sets and Systems, 112 (2003), 327-332.