Content Provider
LeibnizOpen (The Leibniz Association)
19
Unknown
2
Copernicus Publications: E-Journals
1
DataCite Metadata Store (German National Library of Science and Technology)
1
HELDA – University of Helsinki Open Repository
1
Niedersächsisches Online-Archiv NOA
1
Renate - Repositorium für Naturwissenschaften und Technik (TIB Hannover)
1