1. Burns, N. & Grove, S. K. (2005).The practice of nursing research: Conduct, critique, and utilization(5th ed.). St. Louis, MO: Elsevier Saunders.
2. Lincoln, Y. S. & Guba, E. G. (1985).Naturalistic inquiry. Thousand Oaks, CA: Sage.
3. Parahoo, K. (2007).Nursing research principles, process and issues(2nd ed.). New York, NY: Palgrave MacMillan.
4. Rodgers, B. L. (2005).Developing nursing knowledge: Philosophical traditions and influences. Philadelphia, PA: Lippincott Williams & Wilkins.