Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
2,910
Directory of Open Access Journals: DOAJ Articles
1,505
Unknown
1,131
Wiley Online Library (via Crossref)
728
Wiley Online Library
670
PubMed Central (PMC)
510
Springer Nature (via Crossref)
475
PANGAEA - Data Publisher for Earth & Environmental Science
463
Copernicus Publications: E-Journals
316
ScienceDirect (Elsevier - via Crossref)
304
Canadian Science Publishing (via Crossref)
276
MDPI Open Access Publishing
265
University of Calgary Journal Hosting
260
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
248
University of Copenhagen: Research
232
Aarhus University: Research
217
Cambridge University Press
217
Lund University Publications (LUP)
215
Niedersächsisches Online-Archiv NOA
213
University of Tromsø: Munin Open Research Archive
209
Wageningen UR (University & Research Centre): Digital Library
188
LeibnizOpen (The Leibniz Association)
187
Informa (via Crossref)
181
Université de Nantes: HAL-UNIV-NANTES
163
WikiBooks - Open-content textbooks
152
Defense Technical Information Center: DTIC Technical Reports database
150
University of Lethbridge Digitized Collections
143
University of Alaska: ScholarWorks@UA
129
OLAC: Open Language Archives Community
127
LaCRIS - University of Lapland Current Research System
117
HELDA – University of Helsinki Open Repository
116
Institut national des sciences de l'Univers: HAL-INSU
114
Umeå University: Publications (DiVA)
106
Max Planck Society: MPG.PuRe
96
Canadian Science Publishing
93
University of Groningen research database
92
University of California: eScholarship
83
Vrije Universiteit Amsterdam (VU): Research Portal
83
Jultika - University of Oulu repository
80
Zenodo
80
BioOne Online Journals
77
Natural Resources Institute Finland: Jukuri
75
Theses Canada/Thèses Canada (Library and Archives Canada)
73
ScienceDirect (Elsevier)
70
National Institute of Polar Research Repository, Japan
69
University of North Texas: UNT Digital Library
68
NTNU Open Archive (Norwegian University of Science and Technology)
63
Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto
57
HighWire Press (Stanford University)
57
University of Potsdam: publish.UP
55
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