Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
24
Unknown
7
Copernicus Publications: E-Journals
5
HighWire Press (Stanford University)
5
Natural Environment Research Council: NERC Open Research Archive
5
PubMed Central (PMC)
5
ArXiv.org (Cornell University Library)
2
Defense Technical Information Center: DTIC Technical Reports database
2
BioOne Online Journals
1
Lancaster University: Lancaster Eprints
1
MDPI Open Access Publishing
1
Old Dominion University: ODU Digital Commons
1
University of South Carolina Libraries: Scholar Commons
1
W&M ScholarWorks
1
eCite UTAS (University of Tasmania)
1