Crano, Willia, D. <br/><br/>
Principles and methods of social research/ 
William D. Crano and Marilynn B. Brewer 
 - Second Edition ; 
 - New Jersey:  Lawrence Erlbaum Associates,  c2002. 
 - xii, 416 pages :  illustrations ;  25 cm. 
<br/><br/>Includes bibliographical references and index<br/>