1. Mathematics and Applied Sciences Laboratory, Ghardaia University, Ghardaia 47 000, Algeria
2. Department of Mathematics, Hodeidah University, Al-Hudaydah, Yemen
3. Department of Mathematical Sciences, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 84 428, Riyadh 11 671, Saudi Arabia
4. Department of Civil Engineering, College of Engineering, Taif University, P.O. Box 11 099, Taif 21 944, Saudi Arabia