- Biblioteca Digital Camões
- Coursera
- Digital Public Library of America
- Europeana
- Harvard Initiative for Learning and Teaching
- Khan Academy
- The Directory of Open Access Repositories
- Portal do Conhecimento
- Project Gutenberg
- Repositório Científico de Acesso Aberto de Portugal
- Scientific Electronic Library on-line
- World Digital Library
- http://oasisbr.ibict.br/
- http://www.b-on.pt/
- http://www.cplp.org/id-2459.aspx – Biblioteca e Centro de Documentação da CPLP
- http://www.digilibraries.com/
- http://dse.revues.org/ – REVUES.ORG
http://books.openedition.org/ – OPENEDITION.ORG