Content Provider
Unknown
219
Hathi Trust Digital Library
22
University of Calgary Journal Hosting
14
Digital.CSIC (Spanish National Research Council)
11
DataCite Metadata Store (German National Library of Science and Technology)
10
DataCite
9
PANGAEA - Data Publisher for Earth & Environmental Science
9
Wiley Online Library
9
Biodiversity Heritage Library (BHL)
7
University of Wisconsin, Milwaukee: UWM Libraries Digital Collections
6
AAAS Resource Center (American Association for the Advancement of Science)
4
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
4
Arctic Institute of North America
4
Harvard University: Harvard Collections
4
The University of Melbourne: Digitised Collections
4
Zenodo
4
Cambridge University Press
3
Theses Canada/Thèses Canada (Library and Archives Canada)
3
APA Publishing (American Psychological Association)
2
Biblioteca Digital FCEN-UBA (Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires)
2
Indiana Historical Society: Digital Image Library
2
JSTOR (via Crossref)
2
PubMed Central (PMC)
2
ScienceDirect (Elsevier)
2
Springer Nature (via Crossref)
2
AAAS Resource Center (American Association for the Advancement of Science - via Crossref)
1
Bavarian Digital Repository (BDR - Bayerische Staatsbibliothek Munich, BSB)
1
CONICET Digital (Consejo Nacional de Investigaciones Científicas y Técnicas)
1
Canadian Science Publishing
1
Connecticut Digital Archive
1
Dartmouth Digital Commons (Dartmouth College)
1
Directory of Open Access Journals: DOAJ Articles
1
Durham University: Durham Research Online
1
Illinois Library Digital Collections
1
Informa (via Crossref)
1
Institut national de la recherche scientifique, Québec: Espace INRS
1
MSpace at the University of Manitoba
1
MacSphere (McMaster University)
1
Memorial University of Newfoundland: Digital Archives Initiative (DAI)
1
NAOSITE: Nagasaki University Academic Output SITE
1
National Institute of Polar Research Repository, Japan
1
PLOS
1
Project Gutenberg (PG)
1
The University of Vermont: ScholarWorks @ UVM
1
UND Scholarly Commons (University of North Dakota)
1
University of Lincoln: Lincoln Repository
1
University of Michigan: Digital Collections
1
University of New Hampshire: Scholars Repository
1
University of Southern Denmark Research Portal
1
Université Laval: CorpusUL
1
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