Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
506,461
Memorial University of Newfoundland: Digital Archives Initiative (DAI)
242,031
PANGAEA - Data Publisher for Earth & Environmental Science
125,881
Directory of Open Access Journals: DOAJ Articles
105,984
Unknown
85,571
Zenodo
42,597
Wiley Online Library
42,044
Springer Nature (via Crossref)
34,515
University of Michigan: Digital Collections
32,111
ScienceDirect (Elsevier - via Crossref)
29,734
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
26,824
Cambridge University Press
25,422
PubMed Central (PMC)
24,746
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
22,790
ScienceDirect (Elsevier)
20,807
Arctic Data Center (via DataONE)
18,658
University of Washington, Seattle: Digital Collections
18,149
CyberLeninka (Scientific Electronic Library)
17,438
Université de Nantes: HAL-UNIV-NANTES
16,858
Informa (via Crossref)
14,841
LeibnizOpen (The Leibniz Association)
13,501
Copernicus Publications: E-Journals
13,234
Natural Environment Research Council: NERC Open Research Archive
13,146
Institut national des sciences de l'Univers: HAL-INSU
13,122
Open Parks Network
12,990
Defense Technical Information Center: DTIC Technical Reports database
11,329
Research Data Australia (Australian National Data Service - ANDS)
11,249
NOAA NCEI Environmental Data Archive (via DataONE)
10,707
Niedersächsisches Online-Archiv NOA
9,807
National Institute of Polar Research Repository, Japan
9,570
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
9,482
University of Tromsø: Munin Open Research Archive
9,018
Digital.CSIC (Spanish National Research Council)
8,948
Biodiversity Heritage Library (BHL)
8,905
Skemman (Iceland)
8,646
MDPI Open Access Publishing
8,594
David Rumsey Historical Map Collection (Cartography Associates)
8,485
Informa
8,222
University of Copenhagen: Research
8,114
Wiley Online Library (via Crossref)
7,921
Aarhus University: Research
7,840
HighWire Press (Stanford University)
7,637
RePEc (Research Papers in Economics)
7,626
Oxford University Press (via Crossref)
7,146
Hathi Trust Digital Library
7,100
University of California: eScholarship
6,972
Canadian Science Publishing (via Crossref)
6,650
SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy)
6,327
Frontiers: Figshare
6,282
eCite UTAS (University of Tasmania)
6,002
more ...