Content Provider
WikiBooks - Open-content textbooks
38
Unknown
6
IODE-UNESCO: OceanDocs - E-Repository of Ocean Publications
5
Biodiversity Heritage Library (BHL)
4
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center)
2
Australian National University: ANU Digital Collections
2
Flanders Marine Institute (VLIZ): Open Marine Archive (OMA)
2
Texas A&M University Digital Repository
2
Earth-Prints (Istituto Nazionale di Geofisica e Vulcanologia)
1
Frontiers (Publisher)
1
Open Research Library
1
Oxford University Press (via Crossref)
1
The National Academies Press
1
University of Groningen research database
1
University of Southampton: e-Prints Soton
1
University of St Andrews: Research Portal
1
University of Tasmania: UTas ePrints
1
Wiley Online Library
1