Held, Gilbert <br/><br/>
Understanding data communications. 

 - 5th ed. 
 - ix, 368 p.  24cm. 
<br/><br/><label>ISBN: </label>971-8613-69-2 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Data communications.<br/>Telecommunications.<br/>Computer networks.
<br/><br/><label>Dewey Class. No.: </label>004.6 H 366