Science.gov
Science.gov is a gateway to U.S. government science information. The portal offers free access to research and development (R&D) results and scientific and technical information from scientific organizations across 13 federal agencies. Science.gov makes it possible for users to search over 60 databases, over 2,200 websites, and over 200 million pages of authoritative federal science information in many formats, including full-text documents, citations, scientific data supporting federally funded research, and multimedia.