Content Provider
Biodiversity Heritage Library (BHL)
219
WikiBooks - Open-content textbooks
204
IODE-UNESCO: OceanDocs - E-Repository of Ocean Publications
108
Unknown
72
Cambridge University Press
57
Wiley Online Library (via Crossref)
51
National Institute of Polar Research Repository, Japan
36
UNESDOC - UNESCO Digital Library
34
University of Southampton: e-Prints Soton
33
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
32
Flanders Marine Institute (VLIZ): Open Marine Archive (OMA)
29
CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas)
19
Informa (via Crossref)
19
Springer Nature
19
Springer Nature (via Crossref)
18
USRA Houston Repository (Universities Space Research Association)
18
Oxford University Press (via Crossref)
17
OpenAgrar (OA)
16
Australian National University: ANU Digital Collections
13
DataCite Metadata Store (German National Library of Science and Technology)
13
The National Academies Press (via Crossref)
13
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer)
12
Texas A&M University Digital Repository
12
University of Otago: OUR Heritage (Otage University Research)
12
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
11
GEO-LEOe-docs (FID GEO)
11
David Rumsey Historical Map Collection (Cartography Associates)
10
Technical University of Denmark: DTU Orbit
10
Wiley Online Library
10
Ohio State University (OSU): Knowledge Bank
9
De Gruyter
7
JSTOR
7
Open Research Library
7
Oxford University Press
7
Zenodo
7
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
6
Old Dominion University: ODU Digital Commons
6
University of Copenhagen: Research
6
University of Tasmania: UTas ePrints
6
Université de Nantes: HAL-UNIV-NANTES
6
CEDA document repository (Centre for Environmental Data Analysis)
5
Gallica - bibliothèque numérique de la Bibliothèque nationale de France (BnF)
5
Lund University Publications (LUP)
5
RePEc (Research Papers in Economics)
5
The University of Queensland: UQ eSpace
5
University of Bristol: Bristol Research
5
eCite UTAS (University of Tasmania)
5
Digital.CSIC (Spanish National Research Council)
4
IIASA DARE (Data Repository of the International Institute of Applied Systems Analysis)
4
IIASA PURE (International Institute of Applied Systems Analysis: PUblications REpository)
4
more ...