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

 - 6th edition. 
 - New Delhi :  Techmedia,  2007 
 - 619. 
<br/><br/><label>ISBN: </label>8176353191  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Data processing computer science
<br/><br/><label>Dewey Class. No.: </label>004.6  / HEL