A race is on to digitize the world's books, pitting Internet juggernaut Google against a vast anti-Google coalition backed by rivals Yahoo and Microsoft.

In late August, Google restarted its Google Book Search project initiated in 2004 with the lofty aim of scanning every literary work into digital format and making them available online.

Google has formed partnerships with major universities such as Harvard, Oxford, the New York Public Library, Complutense of Madrid and the University of California to add their collections to its virtual book shelves.

In mid-October the University of Wisconsin made its extensive selection of historical works available to the Mountain View, California-based Internet powerhouse.

Google has stored on its searchable database classic works in the public domain, along with copyrighted books either sent with or without the publishers' permission.

Google used its online search expertise to craft search boxes that use keywords, genres and authors to find works as opposed to the romantic practice of sifting through cards in a library reference index.

Google claimed the right of "freedom of quotation" to pull up search results from books.

The virtual library project caused an outcry from publishers and authors that argued Google did not have the right to commandeer their works for free distribution online.

Google has also rejected claims that, being based in the United States, it has favored English. It has promised it would next roll out a Google Book Search in French.

Opposition to the project, particularly by French and US editors, resulted in a group of book publishers forming the Open Content Alliance (OCA) in October of 2005.

The OCA is a non-profit organization which joins together an array of universities, foundations, and data processors to create a "common pot" of digitized books available online for download or printing.

The proposed collection of works contributed by members would consist of 35.000 works, including those of precursors such as the Gutenberg Project.

Initially backed by Sunnyvale, California-based Yahoo, which was to tailor a search engine search engine and finance converting 18,000 books to digital format, the alliance was quickly joined by technology titan Microsoft.

The world's leading computer software company promised to contribute 150,000 digitized books to the OCA collection.

Microsoft also plans to launch its own large-scale virtual book search engine called Windows Live Books Search "later this year," and begin forming its own collection of works.

Microsoft followed Google's lead by asking editors to submit their books to be scanned into digital format free of charge.

Microsoft was working double-time to catch up with Google in the virtual books department.

In mid-October Microsoft signed a deal with Kirtas, a manufacturer of high-speed scanners capable of digitizing an average-length book in eight minutes.

Microsoft also arranged to digitize the contents of the Cornell University library.

Neither Google nor Microsoft would reveal how many books they have already scanned.

"In the thousands," was the only hint Google would give.

At stake for the companies were advertising revenues that could be raked in from book-seeking Internet surfers.

"We are looking into the possibility of incorporating ads into the Windows Live Book Search platform sometime in the future," Microsoft told Associated Press.

The outcome of the battle of the online libraries will undoubtedly hinge on court decisions regarding copyright protections, and which search engine wins over the most coveted collections of written works.

The Open Content Alliance hopes to recruit the National Library of France, where 90,000 books have already been scanned.