Sulkin, Allan <br/><br/>
PBX systems for IP telephony 
Allan Sulkin 
 - New York:  McGraw-Hill,  2002. 
 -  viii, 487p. 
<br/><br/> PB 
<br/><br/><br/>Eng 
<br/><br/><label>ISBN: </label>0071375686 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Communication engineering
<br/><br/><label>Dewey Class. No.: </label>621.382  / SUP