Viswanathan, Thiagarajan. <br/><br/>
Telecommunications switching systems and networks / 

 - 2nd ed. 
 - Delhi :  PHI Learning Pvt. Ltd.,  2020. 
 - xvii, 620 p. :  ill. ;  24 cm. 
<br/><br/> Includes index. 
<br/><br/><label>ISBN: </label>9788120350830 
<br/><br/><label>LC Class. No.: </label>23928-23929 
<br/><br/><label>Dewey Class. No.: </label>621.382  / VIS