Held, Gilbert,  1943- <br/><br/>
Data communications networking devices / 
Gilbert Held 
 - 2nd ed. 
 - Chichester :  John Wiley & Sons,  1989 
 - 494 p. :  ill. ;  26 cm. 
<br/><br/><label>ISBN: </label>0471918695 
<br/><br/><label>LCCN: </label>88-020702 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Computer networks<br/>Data transmission systems