Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
839
CyberLeninka (Scientific Electronic Library)
397
Unknown
176
Defense Technical Information Center: DTIC Technical Reports database
62
PubMed Central (PMC)
38
MDPI Open Access Publishing
29
Copernicus Publications: E-Journals
25
HighWire Press (Stanford University)
15
Institute of Volcanology and Seismology, Petropavlovsk-Kamchatsky: IVS FEB RAS Repository
13
David Rumsey Historical Map Collection (Cartography Associates)
10
University of Nebraska-Lincoln: DigitalCommons@UNL
9
ArXiv.org (Cornell University Library)
6
Washington State University: WSU Libraries Digital Collections
5
Central Washington University: ScholarWorks
2
Boise State University: Scholar Works
1
Digital Repository @ Iowa State University
1
Harvard University: Harvard Collections
1
Ike Skelton Combined Arms Research Library (CARL) Digital Library
1
LSU Digital Commons (Louisiana State University)
1
Open Data LMU (Ludwig-Maximilians-University Munich)
1
Pace University, New York: DigitalCommons@Pace
1
Scientific Publishing Center INFRA - M
1
The College of William & Mary, Williamsburg, Virginia: Digital Archive
1
The College of Wooster: Open Works
1
University of Massachusetts: ScholarWorks@UMass Amherst
1
University of Michigan: Digital Collections
1
University of Rhode Island: DigitalCommons@URI
1
University of Windsor, Ontario: Scholarship at UWindsor
1
University of the Pacific, McGeorge School of Law: Scholarly Commons
1
University of the Pacific: Scholarly Commons
1
W&M ScholarWorks
1