Feyzi Bäar is a Professor Emeritus since July 2016, at Inönü University, Türkiye. He received his PhD from Ankara University, Türkiye, in 1986. He has published four e-books for graduate students and researchers, and more than 160 scientific papers in the field of summability theory, sequence spaces, FK-spaces, Schauder bases, dual spaces, matrix transformations, spectrum of certain linear operators represented by a triangle matrix over some sequence space, the ¿-, ß-, and ¿-duals, and some topological properties of the domains of some two- and four-dimensional triangles in certain spaces of single and double sequences, sets of the sequences of fuzzy numbers, and multiplicative calculus. He has guided 17 master and 10 PhD students and served as a referee for 148 international scientific journals. He is the member of editorial board of 21 scientific journals. Feyzi Bäar is also a member of scientific committee of 17 mathematics conference. He gave talks at 14 different universities as invited speaker and participated more than 70 mathematics symposium with a paper. Bipan Hazarika is Professor in the Department of Mathematics at Gauhati University, Guwahati, Assam. He worked at Rajiv Gandhi University, Rono Hills, Doimukh, Arunachal Pradesh, India from 2005 to 2017. He was Professor at Rajiv Gandhi University up to August 10, 2017. He received his PhD from Gauhati University, Guwahati, India. His main research interests include the field of sequences spaces, summability theory, applications fixed point theory, fuzzy analysis, and function spaces of non-absolute integrable functions. He has published over 200 research papers in several international journals. He is a regular reviewer of more than 50 different journals published from Springer, Elsevier, Taylor and Francis, Wiley, IOS Press, World Scientific, American Mathematical Society, and De Gruyter. He has published books on Differential Equations, Differential Calculus, and Integral Calculus. He has edited books in CRC press on Sequence Spaces, Advances in Mathematical Analysis and its Applications, Dynamic Equations on Time Scales and Applications, and in Springer Nature a book on Fractional Differential Equations and Fixed Point Theory, Approximation Theory, Sequence Spaces and Applications (Industrial and Applied Mathematics), Advances in Functional Analysis and Fixed-Point Theory: An Interdisciplinary Approach (Industrial and Applied Mathematics). In 2022, 2023, and 2024, he was listed among the world's top 2% scientists by Stanford University. He is an editorial board member of more than five International journals and a Guest Editor of the special issue Sequence Spaces, Function Spaces and Approximation Theory, Journal of Function Spaces.
