Hull,L.A. <br/><br/>
Techniques of discussion 
/ L.A.Hill 
. - London  : Evans Brothers Limited, 1980
. - V-58 p.  ; 22 cm. 
<br/><br/><label>ISBN: </label>0237501414 
<br/><br/><label>Source: </label> don 
<br/><br/><label>Universal Decimal Class. No.: </label>8020.0.