Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
3,816
NOAA NCEI Environmental Data Archive (via DataONE)
736
David Rumsey Historical Map Collection (Cartography Associates)
250
Arctic Data Center (via DataONE)
188
PANGAEA - Data Publisher for Earth & Environmental Science
168
Unknown
150
Directory of Open Access Journals: DOAJ Articles
123
Defense Technical Information Center: DTIC Technical Reports database
95
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
67
Copernicus Publications: E-Journals
62
University of Calgary Journal Hosting
44
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
43
Niedersächsisches Online-Archiv NOA
41
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server)
41
LeibnizOpen (The Leibniz Association)
40
Digital.CSIC (Spanish National Research Council)
30
PubMed Central (PMC)
26
University of Tromsø: Munin Open Research Archive
26
Aarhus University: Research
25
Natural Environment Research Council: NERC Open Research Archive
24
University of Southampton: e-Prints Soton
24
Université de Nantes: HAL-UNIV-NANTES
23
Institut national des sciences de l'Univers: HAL-INSU
22
University of Bergen: Bergen Open Research Archive (BORA-UiB)
21
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer)
16
University of Copenhagen: Research
16
Instituto Español de Oceanografía: e-IEO
15
Springer Nature (via Crossref)
15
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
14
Media SuUB Bremen (Staats- und Universitätsbibliothek Bremen)
14
NASA Technical Reports Server (NTRS)
14
Technical University of Denmark: DTU Orbit
14
NIOZ Repository (Royal Netherlands Institute for Sea Research)
13
Naval Postgraduate School: Calhoun
13
OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research)
13
DataCite
12
HighWire Press (Stanford University)
12
Max Planck Society: MPG.PuRe
12
Polar Research (E-Journal)
12
Frontiers: Figshare
11
University College London: UCL Discovery
11
Stockholm University: Publications (DiVA)
10
USGS Science Data Catalog (via DataONE)
10
University of California: eScholarship
10
University of East Anglia: UEA Digital Repository
10
Australian National University: ANU Digital Collections
9
Flanders Marine Institute (VLIZ): Open Marine Archive (OMA)
9
University of New Hampshire: Scholars Repository
9
Wiley Online Library
9
ETH Zürich Research Collection
8
more ...