Content Provider
DataCite Metadata Store (German National Library of Science and Technology)
284
Defense Technical Information Center: DTIC Technical Reports database
256
PANGAEA - Data Publisher for Earth & Environmental Science
150
Unknown
42
Directory of Open Access Journals: DOAJ Articles
39
Universidade de Lisboa: repositório.UL
23
PubMed Central (PMC)
15
The University of Waikato: Research Commons
14
Cambridge University Press
13
IRInSubria - Institutional Repository Insubria (Università degli Studi dell’Insubria)
13
MDPI Open Access Publishing
13
National Institute of Polar Research Repository, Japan
9
ScienceDirect (Elsevier - via Crossref)
9
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
8
Copernicus Publications: E-Journals
8
Digital.CSIC (Spanish National Research Council)
8
Natural Environment Research Council: NERC Open Research Archive
6
Niedersächsisches Online-Archiv NOA
6
Springer Nature (via Crossref)
6
Universidad de Oviedo: RUO
6
Università degli Studi di Ferrara: CINECA IRIS
6
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel)
5
University of California: eScholarship
5
Wiley Online Library (via Crossref)
5
Zenodo
5
Carleton University's Institutional Repository
4
Earth-Prints (Istituto Nazionale di Geofisica e Vulcanologia)
4
IRIS Università degli Studi di Perugia
4
Institut national des sciences de l'Univers: HAL-INSU
4
Lund University Publications (LUP)
4
Masaryk University Journals
4
Ohio State University (OSU): Knowledge Bank
4
Rhodes University Cory: Repository
4
SEALS Digital Commons (South East Academic Libraries System, South Africa)
4
Université de Nantes: HAL-UNIV-NANTES
4
Dialnet - Portada de revistas (Universidad de La Rioja)
3
GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam)
3
LillOA (HAL Lille Open Archive, Université de Lille)
3
Portal de Revistas de la Universidad de La Rioja
3
Saint Petersburg State University: Research Repository (DSpace SPbU)
3
Sapienza Università di Roma: CINECA IRIS
3
University of Canterbury, Christchurch: UC Research Repository
3
University of North Texas: UNT Digital Library
3
University of Zurich (UZH): ZORA (Zurich Open Repository and Archive
3
Università Ca’ Foscari Venezia: ARCA (Archivio Istituzionale della Ricerca)
3
Université du Littoral Côte d'Opale portail
3
ASM Journals (American Society for Microbiology - via Crossref)
2
Aarhus University: Research
2
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer)
2
Australian Nuclear Science and Technology Organisation: ANSTO Publications Online
2
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