Hattingh, Christina.  <br/><br/>
SIP Trunking /  
Hattingh Christina, Sladden Darryl, Swapan Zakaria. 
 - Indianapolis, IN :   Cisco Press,   2010. 
 - XXII, 324 s.:   il.;   24 cm. 
<br/><br/><label>ISBN: </label>9781587059445