Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
2,466
Directory of Open Access Journals: DOAJ Articles
1,621
Wiley Online Library
1,492
Unknown
1,130
PANGAEA - Data Publisher for Earth & Environmental Science
723
DataCite
673
PubMed Central (PMC)
548
Springer Nature (via Crossref)
475
Copernicus Publications: E-Journals
348
MDPI Open Access Publishing
265
University of Calgary Journal Hosting
261
University of Copenhagen: Research
249
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
248
Aarhus University: Research
228
Cambridge University Press
227
Niedersächsisches Online-Archiv NOA
227
ScienceDirect (Elsevier - via Crossref)
224
WikiBooks - Open-content textbooks
224
Lund University Publications (LUP)
218
University of Tromsø: Munin Open Research Archive
218
Canadian Science Publishing
208
LeibnizOpen (The Leibniz Association)
196
Wageningen UR (University & Research Centre): Digital Library
193
Université de Nantes: HAL-UNIV-NANTES
166
Canadian Science Publishing (via Crossref)
165
ScienceDirect (Elsevier)
159
Defense Technical Information Center: DTIC Technical Reports database
150
Informa
149
HELDA – University of Helsinki Open Repository
143
University of Lethbridge Digitized Collections
143
University of Alaska: ScholarWorks@UA
131
OLAC: Open Language Archives Community
127
LaCRIS - University of Lapland Current Research System
125
Institut national des sciences de l'Univers: HAL-INSU
118
Umeå University: Publications (DiVA)
112
Wiley Online Library (via Crossref)
110
Vrije Universiteit Amsterdam (VU): Research Portal
102
Oxford University Press
101
Max Planck Society: MPG.PuRe
100
Zenodo
98
University of Groningen research database
96
Informa (via Crossref)
91
University of California: eScholarship
84
Natural Resources Institute Finland: Jukuri
81
Jultika - University of Oulu repository
80
BioOne Online Journals
78
Theses Canada/Thèses Canada (Library and Archives Canada)
73
Queen's University, Ontario: QSpace
70
National Institute of Polar Research Repository, Japan
69
NTNU Open Archive (Norwegian University of Science and Technology)
68
more ...