Content Provider
Wageningen UR (University & Research Centre): Digital Library
240
University of Groningen research database
212
Flanders Marine Institute (VLIZ): Open Marine Archive (OMA)
209
WikiBooks - Open-content textbooks
123
Unknown
122
Rijksuniversiteit Groningen: University of Groningen Press
89
DataCite Metadata Store (German National Library of Science and Technology)
65
Data Archiving and Networked Services (DANS): EASY (KNAW - Koninklijke Nederlandse Akademie van Wetenschappen)
51
Directory of Open Access Journals: DOAJ Articles
45
Gallica - bibliothèque numérique de la Bibliothèque nationale de France (BnF)
44
Research Institute Nature and Forest: Research outputs
34
KNAW: Research Explorer (Royal Netherlands Academy of Arts and Sciences)
26
Biodiversity Heritage Library (BHL)
22
Ghent University Academic Bibliography
20
Utrecht University Repository
18
Hathi Trust Digital Library
17
KU Leuven: Lirias
16
Doria (National Library of Finland)
15
NIOZ Repository (Royal Netherlands Institute for Sea Research)
15
Vrije Universiteit Amsterdam (VU): Research Portal
15
Project Gutenberg (PG)
14
Delft University of Technology: Institutional Repository
12
Memorial University of Newfoundland: Digital Archives Initiative (DAI)
12
Biblioteca Virtual de Defensa (BVD - Ministerio de Defensa de España)
11
IRUA - Institutional Repository van de Universiteit Antwerpen
10
University of Michigan: Digital Collections
9
National Inst. for Public Health and the Environment, Netherlands (RIVM): Webbased Archive of RIVM Publications (WARP)
8
Vrije Universiteit Brussel (VUB): Research Output
7
Aarhus University: Research
4
Document Server@UHasselt (Hasselt University)
4
Harvard University: Harvard Collections
4
The Portal to Texas History (University of North Texas)
4
Eindhoven University of Technology (TU/e): Research Portal
3
GettDigital (Gettysburg College Digital Collections)
3
Wageningen University & Research Publication System
3
e-rara.ch (ETH Zürich)
3
Bavarian Digital Repository (BDR - Bayerische Staatsbibliothek Munich, BSB)
2
Biblioteca Virtual del Patrimonio Bibliográfico
2
Bulletin KNOB (Koninklijke Nederlandse Oudheidkundige Bond)
2
Creighton University: Creighton Digital Repository (CDR)
2
Maastricht University Research Publications
2
OLAC: Open Language Archives Community
2
Tilburg University: Research portal
2
ULB Düsseldorf: Digitale Sammlungen (University Library of Düsseldorf University)
2
Zenodo
2
e-manuscripta.ch
2
Biblioteca Digital AECID (BIDA, Agencia Española de Cooperación Internacional para el Desarrollo)
1
Center for Jewish History: Digital Collections
1
DIAL@USL-B (Université Saint-Louis, Bruxelles)
1
Digital Library of University of Wroclaw
1
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