Ratzan, Lee <br/><br/>
Understanding information systems  what they do and why we need them 

 - New delhi  Indiana publishing house  2009 
 - xvi,253p.  HB  24cm. 
<br/><br/><label>ISBN: </label>818408238 
<br/><br/><label>Dewey Class. No.: </label>025.04  / RAT