Held, Gilbert <br/><br/>
Understanding Data Communications 
By Gilbert Held 
 - Third Edition 
 -  Global Publishing  1998 
 - 368 pages, 22 cm. 
<br/><br/> includes glossary, bibliographic references & index. 
<br/><br/><label>ISBN: </label>9-71861369-2 
<br/><br/><label>Dewey Class. No.: </label>004.6 H36 C1