1. Google Scholar

2. SINTA_ristek Dikti (Sinta 4)

3. Moraref

4. Dimensions

5. GARUDA-Garba Rujukan Digital

6. International Standard Serial Number

7. OneSearch Indonesia

8. Crossref

9. Leiden University Library

10. Boston University Library

11. University Library

12. Standford Libraries

13. Harvard Library

14. BASE (Bielefeld Academic Search Engine)

15. Semantic Scholar