Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
12,746
Skemman (Iceland)
5,002
Unknown
3,611
OECD iLibrary (via Crossref)
3,399
Hirsla - Landspítali University Hospital research archive
2,737
Directory of Open Access Journals: DOAJ Articles
2,440
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
1,749
Opin vísindi (Iceland)
1,549
Zenodo
1,467
ScienceDirect (Elsevier - via Crossref)
1,411
the Digital Archaeological Record (via DataONE)
1,299
University of Iceland: Peer Reviewed Journals
1,254
RePEc (Research Papers in Economics)
1,200
Springer Nature (via Crossref)
1,068
PubMed Central (PMC)
1,059
PANGAEA - Data Publisher for Earth & Environmental Science
1,052
Université de Nantes: HAL-UNIV-NANTES
1,007
Wiley Online Library (via Crossref)
988
Informa (via Crossref)
886
Wiley Online Library
803
Cambridge University Press
731
HighWire Press (Stanford University)
689
Oxford University Press (via Crossref)
620
University of Copenhagen: Research
532
UNESDOC - UNESCO Digital Library
498
Institut national des sciences de l'Univers: HAL-INSU
495
Aarhus University: Research
492
LeibnizOpen (The Leibniz Association)
438
SAGE Publications (via Crossref)
405
David Rumsey Historical Map Collection (Cartography Associates)
378
Lund University Publications (LUP)
335
MDPI Open Access Publishing
308
Natural Environment Research Council: NERC Open Research Archive
305
ScienceDirect (Elsevier)
301
NOAA NCEI Environmental Data Archive (via DataONE)
296
JSTOR (via Crossref)
290
WikiBooks - Open-content textbooks
290
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
288
GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam)
286
University of Southampton: e-Prints Soton
285
Hathi Trust Digital Library
280
Copernicus Publications: E-Journals
279
North Dakota State University (NDSU): Digital Horizons
265
Springer Nature
246
norden (Nordic Council of Ministers): Publications (DiVA)
245
Defense Technical Information Center: DTIC Technical Reports database
234
Frontiers: Figshare
232
HAL Sorbonne Université
230
CESSDA DC Data Catalogue (Consortium of European Social Science Data Archives)
227
United Nations Publications (via Crossref)
227
more ...