...the researcher tends to have multiple sources of data about the processes within the case study, and thus multiple decisions to make about how to approach data analysis (Schwandt, 2001). (p. 340)

Case Studies: Multiple Sources Of Data
Csaba Osvath

Hays, D. G., & Singh, A. A. (2012). Qualitative Inquiry in Clinical and Educational Settings [electronic resource]. New York : Guilford Press, 2011.