The process and effects of mass communication / 
edited by Wilbur Schramm and Donald F. Roberts. 
 - Urbana :  University of Illinois Press,  1971. 
 - 997 p. :  ill. ;  23 cm. 
<br/><br/>Includes index and references : p. 967-979. 
<br/><br/><label>ISBN: </label>0252001974 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mass media--Congresses.