CCITT GAS 3 Transmission Systems, Economic and Technical Aspects of the Choise of Transmission Systems GAS 3 /   vol.1 

 - Manual-edition1986. 
 - Geneva :   ITU,   1986. 
 - XII, 430 s.:   il.;   30 cm. 
<br/><br/><label>ISBN: </label>9261026516