U.S. publisher HarperCollins said Monday that it plans to <A HREF="http://news.zdnet.com/2100-9595_22-5992116.html?tag=zdnn.alert">convert some 20,000 books</A> in its catalog into digital form in a bid to rein in potential copyright violations on the Internet. The move comes as the U.S. publishing industry is bringing lawsuits against Web search leader Google over its effort to scan copyrighted books in libraries--a move the industry fears would set a dangerous copyright precedent. Chief Executive Jane Friedman said HarperCollins had no immediate plan to raise revenue from the digital copies of the books but it had concluded it was a vital move to protect its authors' rights.