Notes on Intuitionistic Fuzzy Sets Print ISSN 1310–4926, Online ISSN 2367–8283 Vol. 24, 2018, No. 3, 64–78 DOI: 10.7546/nifs.2018.24.3.64-78 Deferred statistical convergence of sequences in intuitionistic fuzzy normed spaces S. Melliani 1 , M. K ¨ uc ¸¨ ukaslan 2 , H. Sadiki 1 and L. S. Chadli 1 1 LMACS, Sultan Moulay Slimane University, BP 523, 23000 Beni Mellal, Morocco e-mails: saidmelliani@gmail.com, sadiki.info@gmail.com, sa.chadli@yahoo.fr 2 Department of Mathematics, Mersin University, Mersin, 33343, Turkey e-mail: mkkaslan@gmail.com Received: 7 April 2018 Revised: 20 October 2018 Accepted: 25 October 2018 Abstract: In this paper, the intuitionistic fuzzy deferred statistical convergence in the intuitionis- tic fuzzy normed space is defined by considering deferred density given in [13]. Besides the main properties of this new method, it is compared with intuitionistic fuzzy statistical convergence and itself under different restrictions on the method. Some special cases of the obtained results are coincided with known results in literature. Keywords: Convergence in intuitionistic fuzzy normed space, Intuitionistic fuzzy deferred con- vergence, Intuitionistic fuzzy deferred statistical convergence. 2010 Mathematics Subject Classification: 03E72, 40A35. 1 Introduction and definitions Fuzzy set theory began with the work of Zadeh [21] in 1965 as an alternative approach to the decision making problems in engineering. Since then, many researchers have been interested in this new subject and many of them have tried to establish whether analogues of classical theories are true or not in the fuzzy case. In the last two decades, fuzzy logic finds application in different areas of science such as non- linear dynamic system [10], control of chaos [8], quantum physics [14], etc. It has also many 64