The up-to-date version of this post will be maintained at http://genweblog.blogspot.com/2007/03/deep-web-search-engines.html
"Google has launched a new Google Scholar search service, providing the ability to search for scholarly literature located from across the web," according to Search Engine Watch. They say,
"The goal is to allow and enable users to search over scholarly content," said Anurag Acharya, a Google engineer leading the project. [Scholarly literature such as peer-reviewed papers, theses, books, preprints, abstracts, and technical reports.]
Much of this material has been added to Google over the past few months. However, the new service allows searchers to specifically search against just the academic material.... Google has worked with publishers to gain access to some material that wouldn't ordinarily be accessible to search spiders, because it is locked behind subscription barriers....
When spidering the content, Google has worked to understand who the authors of the papers are, as well as the formal titles of the papers and other documents that cite the material. These citations are a key part of the special ranking algorithm used by Google for Google Scholar.
Google says the citation extractions allows it to see the connections between papers even if these connections are not made through links. As a result, it can use citation analysis to try and put the best papers at the top of the results. Next to each paper listed is a "Cited by" link. Clicking on this link shows the citation analysis in action -- all the pages pointing at the original one listed, through textual citations, will be shown....
The same paper may be hosted in more than one place, of course. In these instances, Google picks what it believes is the best version and provides links to other versions after the paper's description. In some cases, the material is not actually online. Google may know about a paper only through references it has seen on other papers. In these cases, a Library Search [of WorldCat] and Web Search link will appear next to the paper or book's title.
You can reach Google Scholar here: http://scholar.google.com/
More about it, including FAQs: http://scholar.google.com/scholar/about.html
Other "deep web" or "invisible web" search engines:
- Medical Information Gateways
- Arts and Humanities, and http://websearch.about.com/od/invisibleweb/a/invisiblewebart.htm
- Factbites, an Answer Finding Search Engine
Google Adding Major Libraries to Database: http://valoriez.blogspot.com/2004/12/google-adding-major-libraries-to.html
Google Advanced Search for Genealogy: http://valoriez.blogspot.com/2004/02/google-advanced-search-for-genealogy.html
Google Toolbar as a Win PC Essential: http://valoriez.blogspot.com/2004/09/win-pc-essentials.html
Excess on occasion is exhilarating. It prevents moderation from acquiring the deadening effect of a habit. - W. Somerset Maugham