Houghton, B C <br/><br/>
On line information retrieval systems 
by Houghton, B C and John C  
 - London  Clive Bingley  1977 
<br/><br/><label>ISBN: </label>0851572456 
<br/><br/><label>Dewey Class. No.: </label>025.302854 HOU/ONL