Bogdan, Robert. <br/><br/>
Qualitative Research for Education :  an Introduction to Theories and Methods 
/Robert C. Bogdan, Sari Knopp Biklen. 
 - Fifth ed. 
 - Boston, Mass. :  Pearson A & B,  c2007. 
 - xiv, 304 p. :  ill. ;  24 cm.