Extend your reading even further with these texts!

Hall A. L. and Rist, R. C. (1999) Integrating multiple qualitative research methods (or avoiding the precariousness of a one legged stool). Psychology & Marketing, 16 (4), pp. 291–304.

Whetten, D. (1989) What constitutes a theoretical contribution? Academy of Management Review, 14 (4), pp. 490–495.