Betts, P.W.  <br/><br/>
Supervisory management / 
P.W. Betts. 
 - sixth edition 
 - London :  Pitman publishing,  c 1993. 
 - 422 p. :  ill. 
<br/><br/><label>ISBN: </label>9782 0273600575 
<br/><br/><label>Dewey Class. No.: </label>658.302