Halsall,Fred <br/><br/>
Data communications,computer networks and open systems / 
Halsall,Fred. 
 - 3rd ed. 
 - Workingham:  addison-Wesley,  1992. 
 - xi,772p;26cm 
<br/><br/>Includes bibliographical references. 
<br/><br/><label>ISBN: </label>0201565064 
<br/><br/><label>Dewey Class. No.: </label>004.6 HAL