Johnson, Burke. <br/><br/>
Educational research :  quantitative, qualitative, and mixed approaches / 
By Burke Johnson, Larry B Christensen. 
 - 4th ed. 
 - Thousand Oaks, Calif. :  SAGE Publications, ©2012,  2012. 
 - 621p. ;  00 cm. 
<br/><br/><label>ISBN: </label>9781412978286 
<br/><br/><label>Dewey Class. No.: </label>370.72  / JOH