Content Provider
Washington State University: WSU Libraries Digital Collections
58
Arctic Data Center (via DataONE)
22
USGS Science Data Catalog (via DataONE)
11
DataCite Metadata Store (German National Library of Science and Technology)
5
University of Calgary Journal Hosting
2
University of North Texas: UNT Digital Library
2
Unknown
2
Zenodo
2
Clark University: Clark Digital Commons
1
Dialnet - Portada de revistas (Universidad de La Rioja)
1
Harvard University: Harvard Collections
1
Magnolia press
1
Pensoft Publishers
1