SAO/NASA ADS: ADS Home Page
Operated by the Smithsonian Astrophysical Observatory (SAO) under a NASA grant. The ADS (Astrophysics Data System) maintains three bibliographic databases containing more than 10.4 million records: Astronomy and Astrophysics, Physics, and arXiv e-prints. The main body of data in the ADS consists of bibliographic records, which are searchable through highly customizable query forms, and full-text scans of much of the astronomical literature which can be browsed or searched via a full-text search interface. Integrated in its databases, the ADS provides access and pointers to a wealth of external resources, including electronic articles, data catalogs and archives. They currently have links to over 10.1 million records maintained by their collaborators. Access to full text will depend ofcourse on what your Library has subscriptions to.