Bechhofer, F. (2000). Principles of research design in the Social Sciences. London: Routledge. Ebrary (OUM Digital Library) (TSDAS Digital Library : BF76.5 Whi)

Borg, W., & Borg, M. (1988). Educational research: An introduction. New York: Longman.

Kerlinger, F. (1990). Foundations of behavioural research. New York: Allyn and Bacon. (TSDAS Digital Library : BF76.5 Ker)

Mitchell, M., & Jolley, J. (1988). Research design explained. New York: Holt, Rinehart and Winston. (TSDAS Digital Library : BF76.5 Mit)

Chan, A. (1998). Defining the research problem. Retrieved from: http://www2.fhs.usyd.edu.au/well/knowbase/defresp.htm

Mikijanis, M., & Thom, D. (n. d.). The research question outline. Retrieved from: http://kancrn.kckps.k12.ks.us/guide/question.html

Trochim, W. K.(2006). Problem formulation. Retrieved from: http://www.socialresearchmethods.net/kb/probform.htmBechhofer, F. (2000). Principles of research design in the Social Sciences. London: Routledge. Chapter 1: Fundamentals [available at eBrary].