- A*STAR Open Access Repository (A*OAR)
- Bielefeld Academic Search Engine (BASE)
- COnnecting REpositories (CORE)
- Digital Commons Network
- Directory of Open Access Journals (DOAJ)
- Google Scholar
- JURN
- OAIster
- OpenAIRE
- OpenDOAR (Directory of Open Access Repositories)
- Registry of Open Access Repositories
- GUSTO Data Vault