- OAI-PMH : Open Archives Initiative Protocol for Metadata Harvesting
- OAIster
- OAPEN : Open Access Publishing in European Networks
- OATD : Open Access Theses and Dissertations
- Obra huérfana
- Oceanic Abstratcs
- OCR : Optical Character Recognition
- OCLC : Online Computer Library Center
- OCW : OpenCourseWare
- Offsetting
- OJS : Open Journal System
- OPAC : Catálogo Público de Acceso en Línea
- OpenDOAR
- OpenGrey
- ORCID : Open Research and Contributor ID
- Osiris
Anuncios