Content Provider
LeibnizOpen (The Leibniz Association)
22
Unknown
3
DataCite Metadata Store (German National Library of Science and Technology)
1
Digital Commons University of South Florida (USF)
1
Directory of Open Access Journals: DOAJ Articles
1
Renate - Repositorium für Naturwissenschaften und Technik (TIB Hannover)
1
University of South Florida St. Petersburg: Digital USFSP
1