[1] Guangdong Univ Petrochem Technol, Dept Math, Maoming 525000, Peoples R China
[2] Cent South Univ, Sch Math & Stat, Changsha, Peoples R China
[3] Hubei Univ Automot Technol, Coll Mech Engn, Shiyan 442002, Peoples R China
[4] Qassim Univ, Coll Sci, Dept Math, Buraydah, Saudi Arabia
[5] Northwest Univ, Fac Sci, Dept Math, Kano, Nigeria