Content Provider
Copernicus Publications: E-Journals
14
DataCite Metadata Store (German National Library of Science and Technology)
13
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
9
Niedersächsisches Online-Archiv NOA
8
Springer Nature (via Crossref)
7
Peking University Institutional Repository (PKU IR)
5
PubMed Central (PMC)
5
Zenodo
5
ScienceDirect (Elsevier)
4
Wiley Online Library
4
IOP Publishing
3
NASA Technical Reports Server (NTRS)
3
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
3
ScienceDirect (Elsevier - via Crossref)
3
Cambridge University Press
2
Frontiers (Publisher)
2
PANGAEA - Data Publisher for Earth & Environmental Science
2
MACAU: Open Access Repository of Kiel University
1
National Space Science Center: NSSC OpenIR (Chinese Academy of Sciences)
1
Natural Environment Research Council: NERC Open Research Archive
1
SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy)
1
University of California: eScholarship
1