1. Scopus
  2. EBSCO
  3. Index Copernicus
  4. Embase
  5. Pro Quest
  6. ASI: Advance Science Index (European Science evaluation center)
  7. COPE
  8. DOAJ
  9. Directory of Open Access Scholarly Resources (ROAD)   
  10. Electronic journals Library (EZB)
  11. Ulrichsweb
  12. BASE
  13. International Committee of Medical Journal Editors (ICMJE)
  14. Pablon
  15. Google Scolar
  16. Magiran
  17. SID
  18. Civilica
  19. Journal Index
  20. CiteFactor
  21. INTERNATIONAL INSTITUTE OF ORGANIZED RESEARCH (I2OR)