Babbie, Earl R. <br/><br/>
The practice of social research / 
Earl R. Babbie 
 - 11th ed. 
 - Belmont, CA  :  Wadsworth Publishing ,  2007 
 - 511, [66] p. :  ill. ;  24 cm. 
<br/><br/><label>ISBN: </label>0495093254 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Social sciences--Research<br/>Social sciences--Methodology