CiteSeer

CiteSeer was a public search engine and digital library for scientific and academic papers, primarily in the fields of computer and information science. It had many new features unavailable in academic search engines at that time. These included:

• Autonomous Citation Indexing automatically created a citation index that can be used for literature search and evaluation.
• Citation statistics and related documents were computed for all articles cited in the database, not just the indexed articles.
• Reference linking allowing browsing of the database using citation links.
• Citation context showed the context of citations to a given paper, allowing a researcher to quickly and easily see what other researchers have to say about an article of interest.
• Related documents were shown using citation and word based measures and an active and continuously updated bibliography is shown for each document.

It was replaced by CiteSeerX and all queries to CiteSeer are redirected to it. It is often considered to be the first automated citation indexing system and was considered a predecessor of academic search tools such as Google Scholar and Microsoft Academic Search. CiteSeer-like engines and archives usually only harvest documents from publicly available websites and do not crawl publisher websites. As such authors whose documents are freely available are more likely to be represented in the index.

CiteSeer's goal is to improve the dissemination and access of academic and scientific literature. As a non-profit service that can be freely used by anyone, it has been considered as part of the open access movement that is attempting to change academic and scientific publishing to allow greater access to scientific literature. CiteSeer freely provided Open Archives Initiative metadata of all indexed documents and links indexed documents when possible to other sources of metadata such as DBLP and the ACM Portal.

The name can be construed to have at least two explanations. As a pun, a 'sightseer' is a tourist who looks at the sights, so a 'cite seer' would be a researcher who looks at cited papers. Another is a 'seer' is a prophet and a 'cite seer' is a prophet of citations.