1. Bryman, A., Bell, E.: Business research methods. Oxford University Press, Oxford (2007)
2. Winter, R.: Design science research in Europe. Eur. J. Inf. Syst. 17(5), 470–475 (2008)
3. Cooper, D.R., Schindler, P.S.: Business research methods. McGraw-Hill Education (2003)
4. Zikmund, W., Babin, B., Carr, J., Griffin, M.: Business research methods. Cengage Learning, mason (2012)
5. Tharenou, P., Donohueis, R., Cooper, B.: Management research methods. Cambridge University Press, Cambridge (2007)