Endler, David.  <br/><br/>
Hacking Exposed VoIP :   Voice over IP Security Secrets & Solutions /  
Endler David, Collier Mark. 
 - New York :   McGraw-Hill,   2007. 
 - XXVII, 539 s.:   il.;   23 cm. 
<br/><br/><label>ISBN: </label>9780072263640