Affiliation: | 1. Department of Sciences & Humanities, National University of Computer & Emerging Sciences 44000, Islamabad, Pakistan;2. Department of Mathematics, Quaid-i-Azam University 45320, Islamabad, Pakistan;3. Department of Mathematical Sciences, COMSATS Institute of Information Technology, H-8, Islamabad, Pakistan;4. Department of Mathematics, Technical University of Iasi, Iasi 6600, Romania |