1. Department of Mathematics, Northeast Forestry University, Harbin 150040, China
2. School of Mathematics, Hangzhou Normal University, Hangzhou 311121, China
3. Mathematical Science Department, Faculty of Science, Princess Nourah bint Abdulrahman University, Riyadh 11546, Saudi Arabia
4. Department of Mathematics, College of Science, King Khalid University, Abha 9004, Saudi Arabia
5. North University Center of Baia Mare, Department of Mathematics and Computer Science, Technical University of Cluj Napoca, Victoriei 76, 430122 Baia Mare, Romania