Content Provider
WikiBooks - Open-content textbooks
43
Unknown
33
University of Copenhagen: Research
22
Technical University of Denmark: DTU Orbit
12
Arctic Portal Library
10
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
8
GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam)
8
USRA Houston Repository (Universities Space Research Association)
8
Informa (via Crossref)
7
DataCite Metadata Store (German National Library of Science and Technology)
6
IIASA DARE (Data Repository of the International Institute of Applied Systems Analysis)
6
IIASA PURE (International Institute of Applied Systems Analysis: PUblications REpository)
6
Oxford University Press (via Crossref)
6
The National Academies Press (via Crossref)
6
UNESDOC - UNESCO Digital Library
6
Open Research Library
5
Aarhus University: Research
4
Biodiversity Heritage Library (BHL)
4
Cambridge University Press
4
Frontiers (Publisher)
4
Springer Nature (via Crossref)
4
University of North Texas: UNT Digital Library
4
VTT's Research Information Portal
4
Vrije Universiteit Amsterdam (VU): Research Portal
4
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
3
IRInSubria - Institutional Repository Insubria (Università degli Studi dell’Insubria)
3
OpenAgrar (OA)
3
Springer Nature
3
Texas A&M University Digital Repository
3
University of Zurich (UZH): ZORA (Zurich Open Repository and Archive
3
BORIS (Bern Open Repository and Information System, University of Bern)
2
Digitale Bibliothek Mecklenburg-Vorpommern (Greifswald University)
2
GEO-LEOe-docs (FID GEO)
2
Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto
2
National Research Council Canada: NRC Publications Archive
2
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
2
Oxford University Press
2
RePEc (Research Papers in Economics)
2
Texas Tech University: TTU DSpace Repository
2
University of California: eScholarship
2
University of St Andrews: Digital Research Repository
2
University of Toronto Press (U Toronto Press - via Crossref)
2
Université Grenoble Alpes: HAL
2
Université de Nantes: HAL-UNIV-NANTES
2
ASCE Publications (American Society of Civil Engineers)
1
Ankara University Open Archive System
1
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer)
1
Archivio della ricerca dell'Università di Modena e Reggio Emilia (Unimore: IRIS)
1
Belarusian State University: Electronic Library BSU
1
British Museum Research Repository
1
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