Patton, Michael Quinn. <br/><br/>
Qualitative evaluation and research methods / 
Michael Quinn Patton. 
 - 2nd edition. 
 - Newbury Park, Calif. :  Sage Publications,  1990. 
 - 532 pages :  illustrations ;  23 cm. 
<br/><br/> Rev. ed. of: Qualitative evaluation methods. c1980. 
<br/><br/>Includes bibliographical references (p. 507-523) and index. 
<br/><br/><label>ISBN: </label>9780803937796 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Social sciences --Methodology.<br/>Evaluation research (Social action programs)