Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
448
National Institute of Polar Research Repository, Japan
35
Directory of Open Access Journals: DOAJ Articles
28
Unknown
27
WikiBooks - Open-content textbooks
12
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
11
Zenodo
8
Copernicus Publications: E-Journals
6
David Rumsey Historical Map Collection (Cartography Associates)
6
Institut national des sciences de l'Univers: HAL-INSU
6
Apollo - University of Cambridge Repository
5
University of California: eScholarship
5
Defense Technical Information Center: DTIC Technical Reports database
4
PANGAEA - Data Publisher for Earth & Environmental Science
4
PubMed Central (PMC)
4
Université de Genève: Archive ouverte UNIGE
4
BORIS (Bern Open Repository and Information System, University of Bern)
3
C-RECS (Creative - Repository of Electro Communications)
3
CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas)
3
Digital.CSIC (Spanish National Research Council)
3
Frontiers: Figshare
3
Nanjing Institute of Geology and Palaeontology: NIGPAS OpenIR (Chinese Academy of Sciences)
3
Opin vísindi (Iceland)
3
Springer Nature (via Crossref)
3
The Open University: Open Research Online (ORO)
3
University of Canterbury, Christchurch: UC Research Repository
3
Wiley Online Library
3
Archive de l'Observatoire de Paris (HAL)
2
Australian National University: ANU Digital Collections
2
Biodiversity Heritage Library (BHL)
2
Caltech Authors (California Institute of Technology)
2
Cambridge University Press
2
Digital Commons University of South Florida (USF)
2
Florida Online Journals (FloridaOJ)
2
Frontiers (Publisher)
2
HAL-CEA (Commissariat à l'énergie atomique et aux énergies alternatives)
2
Hathi Trust Digital Library
2
IRD (Institute de recherche pour le développement): Horizon
2
NASA Technical Reports Server (NTRS)
2
Niedersächsisches Online-Archiv NOA
2
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
2
Publication Server of Goethe University Frankfurt am Main
2
Queensland University of Technology: QUT ePrints
2
Research Data Australia (Australian National Data Service - ANDS)
2
Rice University: Digital Scholarship Archive
2
Technical University of Denmark: DTU Orbit
2
The University of Brighton Research Portal
2
UBR (University of Brighton Repository)
2
USGS Science Data Catalog (via DataONE)
2
University of Bergen: Bergen Open Research Archive (BORA-UiB)
2
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