- Creswell, Poth, & Poth, Cheryl N. (2018). Qualitative inquiry & research design : choosing among five approaches (4. ed). SAGE.
- Saunders, M., Lewis, P., & Thornhill, A. (2019). Research methods for business students (8. ed.). Pearson.
- Yin. (2018). Case study research and applications : design and methods (Sixth edition). SAGE.