Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
23
Unknown
12
Borealis
8
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
5
Copernicus Publications: E-Journals
4
PANGAEA - Data Publisher for Earth & Environmental Science
4
Directory of Open Access Journals: DOAJ Articles
3
Niedersächsisches Online-Archiv NOA
3
Zenodo
3
GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam)
2
Defense Technical Information Center: DTIC Technical Reports database
1
Natural Environment Research Council: NERC Open Research Archive
1
Northumbria University, Newcastle: Northumbria Research Link (NRL)
1
Theses Canada/Thèses Canada (Library and Archives Canada)
1
University of Guelph: DSpace digital archive
1
Université de Montréal (UdeM): Papyrus
1