Covey, Stephen R. <br/><br/>
Principle-centred leadership 

 - London :  Pocket books ,  2002. 
 - 020000 
<br/><br/><label>ISBN: </label>9780743468602 
<br/><br/><label>LCCN: </label>2013621531 
<br/><br/><label>LC Class. No.: </label>BF637  / .S8C67 2002