BASE - Bielefeld Academic Search Engine
A multidisciplinary, scientific search engine for bibliographical data of document servers worldwide, selected web sites and local data collections. In some cases, BASE allows a full-text search.
Academically-oriented search engine and citation databank. As well as citation verification, a search gives you bibliographic information, links to full texts, text excerpts, abstracts and related literature. The citation verification indicates where and how often the requested literature has been cited. The advanced search allows you to search by author.
OAIster is one of the most important search engines for open access publications in numerous repositories worldwide.