Communications of the ACM 
Association of the Computer Machinary 
 - New York  Association for Computing Machinery  2003 
 - VOL. 46, ISSUE 9, September 2003 
<br/><br/><label>ISBN: </label>PERIODICAL 
<br/><br/><label>ISSN: </label>00010782 
<br/><br/><label>Dewey Class. No.: </label>621.382 ASS