Run by the U.S. Department of Commerce, NTIS is a clearinghouse for scientific, technical and engineering reports of government-funded research -- some full-text access.
Primary search tool for DOE science, technology, and engineering research and development results and the organizational hub for information about the DOE Office of Scientific and Technical Information -- some full-text access.
This gateway covers over 50 million pages of "authoritative selected science information" provided by U.S. government agencies, including research and development results -- index only, may link to full-text.
The Technical Report Archive & Image Library (TRAIL) identifies, acquires, catalogs, digitizes and provides unrestricted access to U.S. government agency technical reports -- most reports available full-text
Pprovides access to aerospace-related citations, full-text online documents, images, and videos. The types of information included are: conference papers, journal articles, meeting papers, patents, research reports, images, movies, and technical videos – scientific and technical information (STI) created or funded by NASA.
arXiv is an e-print service in the fields of physics, mathematics, non-linear science, computer science, quantitative biology and statistics.
The contents of arXiv conform to Cornell University academic standards. arXiv is owned, operated and funded by Cornell University, a private not-for-profit educational institution. arXiv is also partially funded by the National Science Foundation.
Digital library and search engine that focuses primarily on the scientific literature in computer and information science. Provides citation indexing and statistics.
Online archive of computer science technical reports available for non-commercial use. Participants in NCSTRL include computer science and engineering doctoral-granting universities throughout the world.