Content Provider
Memorial University of Newfoundland: Digital Archives Initiative (DAI)
231,906
PANGAEA - Data Publisher for Earth & Environmental Science
128,658
Directory of Open Access Journals: DOAJ Articles
111,897
DataCite Metadata Store (German National Library of Science and Technology)
73,397
Unknown
56,996
DataCite
54,623
Wiley Online Library
41,449
ScienceDirect (Elsevier - via Crossref)
28,642
Springer Nature (via Crossref)
27,011
PubMed Central (PMC)
26,159
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
23,295
Cambridge University Press
23,103
ScienceDirect (Elsevier)
19,684
Université de Nantes: HAL-UNIV-NANTES
14,833
Copernicus Publications: E-Journals
13,803
LeibnizOpen (The Leibniz Association)
12,765
Institut national des sciences de l'Univers: HAL-INSU
12,633
Open Parks Network
12,595
Defense Technical Information Center: DTIC Technical Reports database
11,329
Niedersächsisches Online-Archiv NOA
9,807
Informa
9,654
Informa (via Crossref)
9,600
MDPI Open Access Publishing
8,594
HighWire Press (Stanford University)
7,642
National Institute of Polar Research Repository, Japan
7,551
University of Copenhagen: Research
7,443
Aarhus University: Research
6,966
Oxford University Press
6,695
University of Tromsø: Munin Open Research Archive
6,548
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
6,500
Hathi Trust Digital Library
6,042
eCite UTAS (University of Tasmania)
6,002
Canadian Science Publishing
5,881
Natural Environment Research Council: NERC Open Research Archive
5,857
Wiley Online Library (via Crossref)
5,815
HAL Sorbonne Université
5,470
Zenodo
5,269
Digital.CSIC (Spanish National Research Council)
5,229
University of Calgary Journal Hosting
5,137
University of St Andrews: Research Portal
5,063
WikiBooks - Open-content textbooks
5,007
Canadian Science Publishing (via Crossref)
4,856
Technical University of Denmark: DTU Orbit
4,273
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer)
4,271
Memorial University of Newfoundland: Research Repository
4,195
Biodiversity Heritage Library (BHL)
4,070
Arctic Council Repository
3,993
Ohio State University (OSU): Knowledge Bank
3,683
Université de Versailles Saint-Quentin-en-Yvelines: HAL-UVSQ
3,571
Oxford University Press (via Crossref)
3,401
more ...