Content Provider
WikiBooks - Open-content textbooks
8
Yale University: EliScholar
5
Unknown
4
Adam Mickiewicz University in Poznań: PRESSto
3
Cambridge University Press
3
Directory of Open Access Journals: DOAJ Articles
2
North Dakota State University (NDSU): Digital Horizons
2
Skemman (Iceland)
2
The Library of Congress: American Memory
2
AMUR - Adam Mickiewicz University Repository, Poznan
1
Akademicka Platforma Czasopism
1
Akademicka Platforma Czasopism (APCZ)
1
CyberLeninka (Scientific Electronic Library)
1
De Gruyter
1
Federation of Finnish Learned Societies: Scientific Journals Online
1
Hirsla - Landspítali University Hospital research archive
1
Hunter Library Digital Collections (Western Carolina University)
1
Jagiellonian University Repository
1
Opin vísindi (Iceland)
1
PennState: Digital Collections
1
RIU - Repositorio Institucional UniLibre (Universidad Libre)
1
RePEc (Research Papers in Economics)
1
Sapienza Università di Roma: CINECA IRIS
1
Swedish University of Agricultural Sciences (SLU): Epsilon Open Archive
1
University of Nebraska Omaha: DigitalCommons@UNO
1
University of West Bohemia Digital Library
1
Universität Bamberg FIS
1
Zenodo
1
Åbo Akademi: Open Journal Systems
1