1. School of Mathematics and Physics China University of Geosciences Wuhan China
2. Department of Mathematics, Faculty of Science Sana'a University Sana'a Yemen
3. School of Mathematics and Statistic Northwestern Polytechnical University Xi'an China
4. Centro de Investigación en Ingeniería y Ciencias AplicadasCIICAp‐IICBA)/UAEM Universidad Autónoma del Estado de Morelos Cuernavaca Mexico
5. Consejo Académico Universidad Virtual CNCI Monterrey Mexico