Babbie, Earl R. <br/><br/>
The basics of social research / 
 Social research. 
Earl Babbie. 
 - 5th ed. 
 - Belmont, CA :  Wadsworth / Cengage Learning,  2011. 
 - xxiii, 552 p. :  ill. ;  24 cm. 
<br/><br/>Includes bibliographical references (p. 531-541) and index. 
<br/><br/><label>ISBN: </label>9780495812241 (pbk.)  RM414.70 0495812242 (pbk.) 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Social sciences--Research.<br/>Social sciences--Methodology.