MartonF. (1978). Describing conceptions of the world around us. (Report No. 66). University of Goteborg, Institute of Education. (ERIC Document Reproduction Service No. ED 169 074).
2.
MartonF. (1988). Phonemenography: A research approach to investigating different conceptions of reality. In FettermanD.M., (ed.), Qualitative approaches to evaluation in education: The silent revolution. Praeger: New York.
3.
StigeBMalterudK., and MidtgardenT. (2009). Toward an agenda for evaluation of qualitative research. Qualitative Health Research. 19(10): 1504–1516.