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

 - 1 
 - USA  SAMS publishing  1994 
 - xvii.435 
<br/><br/><label>ISBN: </label>9780672305016 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Computer Networks
<br/><br/><label>Dewey Class. No.: </label>004.65 HELG