Content Provider
Zenodo
150
USGS Science Data Catalog (via DataONE)
3
Unknown
2
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
1
DataCite Metadata Store (German National Library of Science and Technology)
1
Directory of Open Access Journals: DOAJ Articles
1
Pensoft Publishers
1
University of Kentucky: UKnowledge
1
University of Nebraska-Lincoln: DigitalCommons@UNL
1