Content Provider
Directory of Open Access Journals: DOAJ Articles
434
Unknown
88
WikiBooks - Open-content textbooks
65
LeibnizOpen (The Leibniz Association)
59
DataCite Metadata Store (German National Library of Science and Technology)
46
Copernicus Publications: E-Journals
43
Washington State University: WSU Libraries Digital Collections
37
University of Calgary Journal Hosting
30
PubMed Central (PMC)
28
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
26
Niedersächsisches Online-Archiv NOA
26
University of the Pacific, McGeorge School of Law: Scholarly Commons
25
University of the Pacific: Scholarly Commons
25
Wiley Online Library
22
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer)
19
Defense Technical Information Center: DTIC Technical Reports database
19
Université de Nantes: HAL-UNIV-NANTES
19
Digital.CSIC (Spanish National Research Council)
16
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
15
Natural Environment Research Council: NERC Open Research Archive
13
The University of Utah: J. Willard Marriott Digital Library
13
University of Lethbridge Digitized Collections
12
Cambridge University Press
11
UTSA Digital Collections (The University of Texas at San Antonio)
11
MDPI Open Access Publishing
10
OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research)
9
Springer Nature (via Crossref)
9
University of Southampton: e-Prints Soton
9
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server)
9
eCite UTAS (University of Tasmania)
9
University of Tasmania: UTas ePrints
8
Hunter Library Digital Collections (Western Carolina University)
7
UNESDOC - UNESCO Digital Library
7
CDC Stacks (Centers for Disease Control and Prevention)
6
Institut national des sciences de l'Univers: HAL-INSU
6
National Institute of Polar Research Repository, Japan
6
ScienceDirect (Elsevier - via Crossref)
6
University of British Columbia: cIRcle - UBC's Information Repository
6
Cambridge University Press (via Crossref)
5
Flanders Marine Institute (VLIZ): Open Marine Archive (OMA)
5
GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam)
5
Hathi Trust Digital Library
5
HighWire Press (Stanford University)
5
KRISHI Publication and Data Inventory Repository (Knowledge based Resources Information Systems Hub for Innovations in Agriculture - Indian Council of Agricultural Research, ICAR)
5
Magnolia press
5
Max Planck Society: MPG.PuRe
5
PANGAEA - Data Publisher for Earth & Environmental Science
5
University of Alaska: ScholarWorks@UA
5
CentAUR: Central Archive at the University of Reading
4
DataCite
4
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