Political research methods  : foundations and techniques /   Barbara Leigh Smith ... et al. 

 - Boston:  Houghton Mifflin,  1976. 
 - xiv, 332 p. :  ill. ;   24 cm. 
<br/><br/>Includes index and bibliography: p. 286-303. 
<br/><br/><label>ISBN: </label>0395203635 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Political science--Methodology.<br/>Political science--Research.