1. Bhaskar, R. (1978). A Realist theory of science (3rd ed.). Verso.
2. Collier, A. (1994). An introduction to Roy Bhaskar’s philosophy. Verso.
3. Crotty, M. (1998). The foundations of social research: Meaning and perspective in the research process. Sage.
4. Danermark, B., Ekstrom, L., Jakobsen, L., & Karlsson, J. C. (2002). Explaining society: Critical realism and the social sciences. Routledge.
5. De Leeuw, E. (2009). Evidence for healthy cities: reflections on practice, method and theory. Health promotion international 24(suppl. 1), i19–i36.