Content Provider
LeibnizOpen (The Leibniz Association)
21
DataCite Metadata Store (German National Library of Science and Technology)
3
Unknown
3
Apollo - University of Cambridge Repository
2
Directory of Open Access Journals: DOAJ Articles
2
PANGAEA - Data Publisher for Earth & Environmental Science
1
Renate - Repositorium für Naturwissenschaften und Technik (TIB Hannover)
1
Rice University: Digital Scholarship Archive
1
The University of Adelaide: Digital Library
1
Utrecht University Repository
1