1. Department of Theoretical Physics, Faculty of Physics, Baku State University, Z. Khalilov St. 23, AZ-1148, Baku, Azerbaijan
2. CERN, Theoretical Physics Department, CH-1211 Geneva 23, Switzerland
3. COMSATS Institute of Information Technology, Park-Road, Chak-Shahzad, 44000, Islamabad, Pakistan
4. Institute of Physics, Azerbaijan National Academy of Sciences, H. Javid Avenue, 131, AZ-1143, Baku, Azerbaijan