Content Provider
University of Michigan: Digital Collections
80
Hathi Trust Digital Library
27
Bavarian Digital Repository (BDR - Bayerische Staatsbibliothek Munich, BSB)
15
OLAC: Open Language Archives Community
8
Yale University: EliScholar
8
DataCite Metadata Store (German National Library of Science and Technology)
5
Harvard University: Harvard Collections
4
Princeton Theological Seminary: Theological Commons
4
norden (Nordic Council of Ministers): Publications (DiVA)
3
Digital Collections of Colorado (Colorado State University)
1
Mountain Scholar (Digital Collections of Colorado and Wyoming)
1
Project Gutenberg (PG)
1
The Library of Congress: American Memory
1