Bogart, Leo. <br/><br/>
Silent politics:   polls and the awareness of public opinion / 
by Leo Bogart. 
 - New York :  John wiley & sons,  1972. 
<br/><br/><label>ISBN: </label>0471085200 
<br/><br/><label>Dewey Class. No.: </label>301.1542  / BOG.S