Bogdan, R. C., & Biklen, S. K. (2007). Qualitative research for education: An introduction to theories and methods (International 5th ed.). Boston, Mass. ; New York: Pearson A & B.

Bogdan, Robert C., and Sari Knopp Biklen. Qualitative Research for Education: An Introduction to Theories and Methods. International 5th ed. Boston, Mass. ; New York: Pearson A & B, 2007.

Bogdan, Robert C., and Sari Knopp Biklen. Qualitative Research for Education: An Introduction to Theories and Methods. International 5th ed. Boston, Mass. ; New York: Pearson A & B, 2007.