Kessler, Gary C. <br/><br/>
ISDN  Concepts, Facilities and services 
Kessler, Gary C. 
 - 2nd ed. 
 - USA  The McGraw-Hill  1993 
 - xviii, 454 p. ;  ill. ;  24 cm. 
<br/><br/> Includes bibliographical references. 
<br/><br/><label>ISBN: </label>0071139338 
<br/><br/><label>Subjects--Topical Terms: </label><br/>1. Integrated services digital networks.
<br/><br/><label>Dewey Class. No.: </label>621.382