Notes on Intuitionistic Fuzzy Sets Print ISSN 1310–4926, Online ISSN 2367–8283 Vol. 27, 2021, No. 4, 20–29 DOI: 10.7546/nifs.2021.27.4.20-29 Modiﬁcations of the Goguen’s intuitionistic fuzzy implication Janusz Kacprzyk 1 , Katar´ ına ˇ Cunderl´ ıkov´ a 2 , Nora Angelova 3 and Krassimir T. Atanassov 4 1 Systems Research Institute, Polish Academy of Sciences ul. Newelska 6, 01-447 Warsaw, Poland, and Warsaw School of Information Technology ul. Newelska 6, 01-447 Warsaw, Poland e-mail: kacprzyk@ibspan.waw.pl 2 Mathematical Institute, Slovak Academy of Sciences ˇ Stef´ anikova 49, 814 73 Bratislava, Slovakia e-mail: cunderlikova.lendelova@gmail.com 3 Faculty of Mathematics and Informatics, Soﬁa University 5 James Bourchier Blvd., 1164 Soﬁa, Bulgaria e-mail: nora.angelova@fmi.uni-sofia.bg 4 Department of Bioinformatics and Mathematical Modelling, Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences 105 Acad. G. Bonchev Str., 1113 Soﬁa, Bulgaria e-mail: krat@bas.bg Received: 21 July 2021 Accepted: 20 November 2021 Abstract: On the basis of the Goguen’s intuitionistic fuzzy implication, seven of its modiﬁcations are constructed. Some of their basic properties are studied. The negations, generated by these implications are introduced and some of their properties are also described. Keywords: Intuitionistic fuzzy implication, Intuitionistic fuzzy pair, Goguen’s fuzzy implication. 2020 Mathematics Subject Classiﬁcation: 03E72. 20