BASE—Bielefeld Academic Search Engine
It seeks “intellectually selected resources” that meet academic quality standards and “web resources of the ‘Deep Web,’ including more than 30 million documents in several languages
Fee-based resource that offers access to articles and journals to the general public
MedNar: Deep Web Medical Search
Free search engine utilizing federated search for medical resources
Offers all things physics
WorldWideScience.org: The Global Science Gateway
This database is the product of an alliance among international scientific institutions and is operated by the US Department of Energy
