Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
192
University of Washington, Seattle: Digital Collections
73
Arctic Data Center (via DataONE)
45
Zenodo
35
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
18
Unknown
10
Directory of Open Access Journals: DOAJ Articles
8
ESS-DIVE: Deep Insight for Earth Science Data (via DataONE)
8
Cambridge University Press (via Crossref)
5
Washington State University: WSU Libraries Digital Collections
5
University of the Pacific, McGeorge School of Law: Scholarly Commons
4
University of the Pacific: Scholarly Commons
4
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
3
Canadian Science Publishing (via Crossref)
3
CyberLeninka (Scientific Electronic Library)
3
Frontiers: Figshare
3
PANGAEA - Data Publisher for Earth & Environmental Science
3
Perm State University: Publications of Geological Faculty
3
University of British Columbia: cIRcle - UBC's Information Repository
3
University of Calgary Journal Hosting
3
Université de Nantes: HAL-UNIV-NANTES
3
Copernicus Publications: E-Journals
2
Defense Technical Information Center: DTIC Technical Reports database
2
Durham University: Durham Research Online
2
OSKAR Bordeaux (Open Science Knowledge ARchive)
2
WikiBooks - Open-content textbooks
2
Wiley Online Library (via Crossref)
2
Arctic Institute of North America (via Crossref)
1
BioOne Online Journals
1
Boise State University: Scholar Works
1
Brill (via Crossref)
1
Cambridge University Press
1
Canadian Science Publishing
1
Carolina Digital Repository (UNC - University of North Carolina)
1
Central Washington University: ScholarWorks
1
Digital Commons University of South Florida (USF)
1
Dryad Digital Repository (Duke University)
1
Federation of Finnish Learned Societies: Scientific Journals Online
1
IEDA: EarthChem Library (via DataONE)
1
Institut national des sciences de l'Univers: HAL-INSU
1
Lancaster University: Lancaster Eprints
1
MDPI Open Access Publishing
1
Magnolia press
1
Max Planck Society: MPG.PuRe
1
Murdoch University: Murdoch Research Repository
1
Niedersächsisches Online-Archiv NOA
1
North Dakota State University (NDSU): Digital Horizons
1
Oxford University Press
1
Oxford University Press (via Crossref)
1
Padua Research Archive (IRIS - Università degli Studi di Padova)
1
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