[Song, Ying-Qing] Hunan City Univ, Coll Sci, Yiyang 413000, Peoples R China.
[Imran, M.; Waqas, Hassan; Farooq, Umar] Govt Coll Univ Faisalabad, Dept Math, Faisalabad 38000, Pakistan.
[Al-Khaled, Kamel] Jordan Univ Sci & Technol, Dept Math & Stat, POB 3030, Irbid 22110, Jordan.
[Gouadria, Soumaya] Princess Nourah Bint Abdulrahman Univ, Coll Sci, Dept Phys, POB 84428, Riyadh 11671, Saudi Arabia.
[Khan, Sami Ullah] COMSATS Univ Islamabad, Dept Math, Sahiwal 57000, Pakistan.