Merriam, S. B., & Tisdell, E. J. (2016). Qualitative research : a guide to design and implementation (Fourth edition.). Jossey-Bass, a Wiley Brand. Read Chapter 1
Merriam, S. B., & Grenier, R. S. (2019). Qualitative research in practice : examples for discussion and analysis (Second edition.) Jossey-Bass. Read pages 33-86.