1. S.G.R.R. (P.G.) College, Dehradun, India
2. Government Degree College Thatyur (Tehri Garhwal), Uttarakhand, India
3. Department of Mathematics, College of Science and Humanities in Alkharj, Prince Sattam bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia
4. Department of Basic Engineering Sciences, Faculty of Engineering, Menofia University, Menofia, Egypt
5. Department of Mathematics and Computer Science, St. Thomas College, Bhilai, Durg, India