Wilson, Graham K. <br/><br/>
Interest groups in the United States/ 
Graham K. Wilson. 
 - Oxford  Clarendon Press  1981. 
 - ix,161 p. ;  22 cm. 
<br/><br/>Includes index and bibliography : p154-158. 
<br/><br/><label>ISBN: </label>0198274254 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Pressure groups--United States