[1] Akram, M. (2018). Fuzzy lie algebras. Springer.
[2] Atanassov, K. T. (1986). Intuitionistic fuzzy sets. Fuzzy sets and system, 20, 87-96.
[3] Atanassov, K. T., & Gargov, G. (1989). Interval valued intuitionistic fuzzy sets. Fuzzy sets and systems, 31, 343-349.
[4] Chen, T. Y. (2018). An interval valued Pythagorean fuzzy outranking method with a closeness-based assignment model for multiple criteria decision making. International journal of intelligent systems, 33(1), 126-168.
[5] Chen, T. Y. (2018). An outranking approach using a risk attitudinal assignment model involving Pythagorean fuzzy information and its application to financial decision making. Applied soft computing, 71(1), 460-487.
[6] Das, S., & Edalatpanah, S. A. (2016). A general form of fuzzy linear fractional prograss with trapezoidal fuzzy numbers. International journal of data envelopment analysis and operations research, 2(1), 16-19.
[7] Edalatpanah, S. A. (2019). A data envelopment analysis model with triangular intuitionistic fuzzy numbers. International journal of data envelopment analysis, 2(1), 16-19.
[8] Garg, H. (2018). A linear programming method based on an improved score function for interval valued Pythagorean to decision making. International journal of uncertainty, fuzziness and knowledge based systems, 26(1), 67-80.
[9] Garg, H. (2018). New exponential operational laws and their aggregation operators for interval valued pythagorean fuzzy multicriteria decision making. International journal of intelligent systems, 33(3), 653-683.
[10] Hussain, A., Mahmood, T., & Ali, M. I. (2019). Rough Pythagorean fuzzy ideals in semigroups. Computational and applied mathematics, 38(2), 67.
[11] Kumar, R., Edalatpanah, S. A., Jha, S., & Sing, R. (2019). A Pythagorean fuzzy approach to the transportation. Complex and intelligent systems, 5(2), 255-263.
[12] Najafi, H. S., & Edalatpanah, S. A. (2013). Iterative methods with analytical preconditioning technique to linear complementarity problems: application to obstacle problems. RAIRO-operations research, 47(1), 59-71.
[13] Peng, X. (2019). New operations for interval valued Pythagorean fuzzy set. Scientia iranica, 26(2), 1049-1076.
[14] Peng, X., & Yang, Y. (2016). Fundamental properties of interval valued pythagorean fuzzy aggregation operators. International journal of intelligent systems, 31(5), 444-487.
[15] Thillaigovindan, N., & Chinnadurai, V. (2009). On interval-valued fuzzy quasi-ideals of semigroups. East Asian mathematical journal, 25(4), 441-453.
[16] Thillaigovindan, N., & Chinnadurai, V. (2009). Interval-valued fuzzy generalized bi-ideals. Proceedings of the national conference on algebra, graph theory and their applications (pp. 85-98). Department of Mathematics, Manonmaniam Sundaranar University, Narosa.
[17] Yager, R. R. (2013, June). Pythagorean fuzzy subsets. In 2013 joint IFSA world congress and NAFIPS annual meeting (IFSA/NAFIPS) (pp. 57-61). IEEE.
[18] Zadeh, L. A. (1965). Fuzzy sets. Information and control, 8, 338-353.
[19] Zadeh, L. A. (1975). The concept of a linguistic variable and its application to approximate reasoning –I. Information science, 8, 199-249.
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