Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
769
LeibnizOpen (The Leibniz Association)
19
Zenodo
16
Unknown
11
WikiBooks - Open-content textbooks
10
Wiley Online Library
4
Hathi Trust Digital Library
3
North Dakota State University (NDSU): Digital Horizons
3
RePEc (Research Papers in Economics)
3
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
2
DRO - Deakin Research Online
2
Digital.CSIC (Spanish National Research Council)
2
Directory of Open Access Journals: DOAJ Articles
2
Jultika - University of Oulu repository
2
Middlesex University London: Research Repository
2
National Library of Australia: Digital Collections
2
Prince of Songkla University: PSU Knowledge Bank
2
Skemman (Iceland)
2
UPF Digital Repository (Universitat Pompeu Fabra, Barcelona)
2
University of Southampton: e-Prints Soton
2
Washington State University: WSU Libraries Digital Collections
2
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
1
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer)
1
Arctic Council Repository
1
Ardabil University of Medical Sciences: Research Information Management System
1
Australian Policy Online (Institute for Social Research, Swinburne University of Technology)
1
Avondale College: ResearchOnline@Avondale
1
Brigham Young University (BYU): Digital Collections
1
Bushehr University of Medical Sciences Repository
1
CESSDA DC Data Catalogue (Consortium of European Social Science Data Archives)
1
CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas)
1
Cambridge University Press
1
Canadian Science Publishing (via Crossref)
1
Copernicus Publications: E-Journals
1
David Rumsey Historical Map Collection (Cartography Associates)
1
Defense Technical Information Center: DTIC Technical Reports database
1
Digital Repository of University of Zaragoza (ZAGUAN)
1
Dokuz Eylül University Research Information System
1
Epistemological studies in Philosophy, Social and Political Sciences (E-Journal)
1
Erasmus University Rotterdam & Erasmus MC Research Portal
1
Flanders Marine Institute (VLIZ): Open Marine Archive (OMA)
1
Frontiers (Publisher)
1
Ghent University Academic Bibliography
1
Griffith University: Griffith Research Online
1
HELDA – University of Helsinki Open Repository
1
HighWire Press (Stanford University)
1
Hunter Library Digital Collections (Western Carolina University)
1
Høgskulen på Vestlandet: HVL Open
1
IEDA: EarthChem Library (via DataONE)
1
IRD (Institute de recherche pour le développement): Horizon
1
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