Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
12,184
Unknown
244
Directory of Open Access Journals: DOAJ Articles
155
Zenodo
143
CESSDA DC Data Catalogue (Consortium of European Social Science Data Archives)
100
Arctic Council Repository
84
RePEc (Research Papers in Economics)
82
North Dakota State University (NDSU): Digital Horizons
70
Defense Technical Information Center: DTIC Technical Reports database
54
ESS-DIVE: Deep Insight for Earth Science Data (via DataONE)
53
University of Tromsø: Munin Open Research Archive
47
da|ra - Registration agency for social and economic data
46
PubMed Central (PMC)
44
Cambridge University Press
41
LeibnizOpen (The Leibniz Association)
39
WikiBooks - Open-content textbooks
33
UNESDOC - UNESCO Digital Library
31
WHO (World Health Organization): Institutional Repository for Information Sharing (IRIS)
31
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
27
Kew Research Repository
22
Dryad Digital Repository (Duke University)
19
Digital.CSIC (Spanish National Research Council)
18
Copernicus Publications: E-Journals
17
University of Calgary Journal Hosting
17
CyberLeninka (Scientific Electronic Library)
16
DergiPark Akademik (E-Journals)
15
Institute for Marine Research: Brage IMR
15
MDPI Open Access Publishing
15
University of Tromsø: Septentrio Academic Publishing
15
NTNU Open Archive (Norwegian University of Science and Technology)
14
Norwegian Institute for Nature Research: Brage NINA
14
USGS Science Data Catalog (via DataONE)
14
Universitet i Oslo: Digitale utgivelser ved UiO (DUO)
14
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer)
13
Frontiers: Figshare
13
LaCRIS - University of Lapland Current Research System
13
University of Lethbridge Digitized Collections
13
CDC Stacks (Centers for Disease Control and Prevention)
12
Magnolia press
12
Niedersächsisches Online-Archiv NOA
12
University of Leicester: Leicester Research Archive (LRA)
12
Université de Nantes: HAL-UNIV-NANTES
12
Aarhus University: Research
11
Arctic Portal Library
11
Canadian Science Publishing (via Crossref)
11
University of Bergen: Bergen Open Research Archive (BORA-UiB)
11
Wiley Online Library (via Crossref)
11
Arctic Data Center (via DataONE)
10
LAEI VL (Lithuanian Institute of Agrarian Economics Virtual Library)
10
LSRC VL (Lithuanian Social Research Centre Virtual Library)
10
more ...