Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
415
Directory of Open Access Journals: DOAJ Articles
71
CyberLeninka (Scientific Electronic Library)
36
Aarhus University: Research
32
Norwegian Institute for Nature Research: Brage NINA
26
Unknown
22
Springer Nature (via Crossref)
21
Wiley Online Library
21
PubMed Central (PMC)
19
Zenodo
17
IRUA - Institutional Repository van de Universiteit Antwerpen
16
LAEI VL (Lithuanian Institute of Agrarian Economics Virtual Library)
15
LSRC VL (Lithuanian Social Research Centre Virtual Library)
15
NTNU Open Archive (Norwegian University of Science and Technology)
15
ScienceDirect (Elsevier - via Crossref)
14
University of Copenhagen: Research
13
University of Turku: UTUPub
9
MDPI Open Access Publishing
8
University of Tromsø: Munin Open Research Archive
7
ACS Publications
6
Cardiff University: ORCA (Online Research @ Cardiff)
6
Croatian Digital Theses Repository (National and University Library in Zagreb)
6
Edinburgh DataShare (University of Edinburgh)
6
Federation of Finnish Learned Societies: Scientific Journals Online
6
ScienceDirect (Elsevier)
6
University of Liège: ORBi (Open Repository and Bibliography)
6
Vilnius University Virtual Library (VU VL)
6
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
5
Cambridge University Press
5
Dryad Digital Repository (Duke University)
5
NILU – Norwegian Institute for Air Research: NILU Brage
5
Wiley Online Library (via Crossref)
5
De Gruyter (via Crossref)
4
Flanders Marine Institute (VLIZ): Open Marine Archive (OMA)
4
Informa (via Crossref)
4
Lund University Publications (LUP)
4
Swedish environmental protection agency: Publications (DiVA)
4
Université de Nantes: HAL-UNIV-NANTES
4
De Gruyter
3
DergiPark Akademik (E-Journals)
3
HAL - Université de La Rochelle
3
HELDA – University of Helsinki Open Repository
3
Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto
3
Jultika - University of Oulu repository
3
TÜBİTAK Academic Journals
3
University of the Balearic Islands (UIB): Digital Library
3
Uppsala University: Publications (DiVA)
3
Vytautas Magnus University e-Publication Repository (VMU ePub)
3
Bergen Open Access Publishing (University of Bergen Library)
2
Biodiversity Heritage Library (BHL)
2
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