1. School of Finance and Accounting, Fuzhou University of International Studies and Trade, Fuzhou 352020, P. R. China
2. Faculty of Business, City university of Macau, Macau 999078, P. R. China
3. Department of Mathematics and Statistics, University of Neyshabur, Neyshabur, Iran
4. CONACyT-Tecnológico Nacional de México/CENIDET, Interior Internado Palmira S/N, Col. Palmira, C.P. 62490, Cuernavaca, Morelos, México