Affiliation: | 1. Department of Mathematics, COMSATS Institute of Information Technology, Lahore-54000, Pakistan;2. Department of Mathematics, Kohat University of Science and Technology, Kohat, Pakistan;3. Department of Mathematics, School of Natural Sciences(SNS), National University of Sciences and Technology(NUST) H-12, Islamabad, Pakistan;4. Department of Mathematics, Indian Institute of Engineering Science and Technology, Shibpur, Howrah-711 103, India |