Ratzan, Lee. <br/><br/>
Understanding information systems  : what they do and why we need them 
/ by Lee Ratzan. 
 - New Delhi :  Indian Publishing house,  2009. 
 - 253 p. 
 - Understanding library association series .
<br/><br/><label>ISBN: </label>818408238X 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Library  science<br/>Information science<br/>Library operations<br/>Information storage<br/>Information retrieval system<br/>Information system
<br/><br/><label>Dewey Class. No.: </label>025.04  / RAT