Dang, Luan. <br/><br/>
Practical VoIP using VOCAL / 
Luan Dang, Cullen Jennings, and David Kelly. 
 - 1st ed. 
 - Beijing ;  Sebastopol, CA :  O'Reilly,  2002. 
 - xvii, 502 p. :  ill. ;  24 cm. 
<br/><br/> Includes index. 
<br/><br/><label>ISBN: </label>0596000782 
<br/><br/><label>LCCN: </label>2002023323 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Internet telephony.
<br/><br/><label>LC Class. No.: </label>TK5105.8865  / .D35 2002 
<br/><br/><label>Dewey Class. No.: </label>621.382/12