Dahl, Robert Alan <br/><br/>
Polyarchy    participation and opposition. 

 - New Haven   Yale University Press    1971 
 - 257 p. 
<br/><br/><label>ISBN: </label>978-0300-01565-2. 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Political opposition<br/> Political participation<br/>Opposition (Political science)<br/>Political science