Scirus distinguishes itself from existing search engines by concentrating on scientific content only and by searching both web and (often proprietary) databases. Search engines generally index the web by letting a robot crawl websites. However, a lot of information on the Web is invisible to search engines, because they are either not allowed on the site or are technically not capable of crawling them. Sixty percent of the information on the Web is thought to be "invisible" in this way. Scirus' aim is to provide scientists with one comprehensive search platform covering both the web and the normally "invisible" databases.

For more information, please see http://www.scirus.com/about/.

Contact

• ArXiv at http://ArXiv.org
• Chemistry Preprint Server at http://www.chemweb.com
• Cogprints at http://cogprints.ecs.soton.ac.uk/
• Computer Science Preprint Server at http://www.compscipreprints.com
• Mathematics Preprint Server at http://www.mathpreprints.com
• Langley Technical Reports Server at http://techreports.larc.nasa.gov/ltrs/
• National Advisory Committee for Aeronautics Technical Reports Server at hhttp://naca.larc.nasa.gov/