Content Provider
David Rumsey Historical Map Collection (Cartography Associates)
405
DataCite Metadata Store (German National Library of Science and Technology)
256
Hathi Trust Digital Library
85
Biodiversity Heritage Library (BHL)
29
The University of Utah: J. Willard Marriott Digital Library
24
Penn Press - University of Pennsylvania Press
22
Temple University Digital Collections
17
University of Michigan: Digital Collections
13
Defense Technical Information Center: DTIC Technical Reports database
8
University of the Pacific, McGeorge School of Law: Scholarly Commons
7
University of the Pacific: Scholarly Commons
7
Unknown
7
Directory of Open Access Journals: DOAJ Articles
6
University of Michigan: Deep Blue
6
National Chengchi University Institutional Repository (NCCUIR)
4
Texas Tech University: TTU DSpace Repository
4
APS Digital Library (American Philosophical Society)
3
Harvard University: Harvard Collections
3
North Dakota State University (NDSU): Digital Horizons
3
The Online Books Page (Penn Libraries, University of Pennsylvania)
3
University of Calgary Journal Hosting
3
University of Wisconsin, Milwaukee: UWM Libraries Digital Collections
3
Bavarian Digital Repository (BDR - Bayerische Staatsbibliothek Munich, BSB)
2
BioOne Online Journals
2
Brigham Young University (BYU): Digital Collections
2
Cambridge University Press (via Crossref)
2
HighWire Press (Stanford University)
2
Informa (via Crossref)
2
Philadelphia College of Osteopathic Medicine: DigitalCommons@PCOM
2
PubMed Central (PMC)
2
Scientia Marina (E-Journal)
2
Tamkang University Institutional Repository (TKUIR) / 淡江大學機構典藏
2
University of Otago: Research Archive (OUR Archive)
2
Washington State University: WSU Libraries Digital Collections
2
York University Digital Library
2
Aarhus University: OJS at The State and University Library
1
Antiquity
1
ArXiv.org (Cornell University Library)
1
Bergen Open Access Publishing (University of Bergen Library)
1
Cambridge University Press
1
Canadian Science Publishing (via Crossref)
1
Center for Jewish History: Digital Collections
1
Collectanea Botanica (E-Journal)
1
Connecticut Digital Archive
1
Digital Repository of Scientific Institutes (RCIN)
1
Docta Complutense (Universidad Complutense de Madrid - UCM)
1
Doria (National Library of Finland)
1
Drexel University: iDEA - Drexel Libraries E-Repository And Archives
1
Earth-Prints (Istituto Nazionale di Geofisica e Vulcanologia)
1
Edinburgh University Press (via Crossref)
1
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