“…Some of the most influential pioneer works on the subject are, among others, those by Ruspini (1969Ruspini ( , 1970, Tamura et al (1971), Dunn (1973Dunn ( , 1974, Bezdek (1973Bezdek ( , 1974Bezdek ( , 1980, and Bezdek et al (1984), which have inspired both applications and many further methodologies. At present, this is one of the most successful topics involving Fuzzy Sets and Statistical theories, and the number of research papers on it is unquestionably growing [among the most recent ones see, for instance, the approaches in Liu et al (2013), Gong et al (2014), Yamashita and Mayekawa (2015), Ruan et al (2016), and Nguyen-Trang and Vo- Van (2017)], and it appears often either combined with or supporting other data analysis problems. In more detail, useful references to the extensive literature on the fuzzy clustering (from both theoretical and applicative points of view) can be found in the chapter on the fuzzy clustering by D'Urso (2016), the seminal monograph by Bezdek (1981), the books by Jain and Dubes (1988), De Oliveira and Pedrycz (2007), Miyamoto et al (2008) As remarked by D'Urso (2017a), there are different uncertainty-based clustering methods that can be considered extensions, variants and alternatives of the fuzzy clustering for non-fuzzy/standard data, like -possibilistic clustering [see, for instance, Krishnapuram and Keller (1993)], -shadowed clustering [see, for instance, Pedrycz (1998) Fuzzy approaches to analyze crisp/standard data, have not been carried out as exhaustively as fuzzy clustering ones for the same data.…”