General
BASE – Bielefeld Academic Search Engine
Bielefeld Academic Search Engine External link. and index for academic resources contains about 120 million documents. Around 60 % of its indexed content is open access.
CORE
CORE’s External link. search engine and index for aggregated research publications from repositories and journals globally. Developed by JISC and the Open University it offers access to around 133 million articles.
Dimensions
Apart from searching for publications and the possibility to search for cited and citing articles, Dimensions External link. also indexes grants, patents, and clinical trials. The free version offers limited possibilities.
DOAJ
DOAJ External link. is a list of open access journals and a search service finding peer-reviewed and scholarly journals and articles.
Google Scholar
Google Scholar External link. is an index and search engine for academic content on the web.
OpenDOAR
OpenDOAR External link. is a searchable global directory of open access repositories and their policies.
OSF Preprints
OSF Preprints External link. is a platform with openly accessible preprints, or submitted manuscripts which are publically distributed before acceptance and peer-review in a traditional scientific journal. An advantage of publishing preprints is the speeding up of scientific communication and of sharing research results earlier, as it can take a long time between submission of an article till publication.
OSF Preprints is developed by Centre for Open Science (COS), a non-profit organisation with the goal of greater openness and reproducible research.
Zenodo
Zenodo External link. is an open archive developed by CERN where researchers can deposit publications, preprints, software, and research data.