1. Abedi,H A, Maggs, C. Identifying the health needs of elderly people using the Omaha Classification Scheme Journal of advanced nursing. 1996.
2. Burns, N. S. Grove K, (2008) The Practice of Nursing Research: Conduct, Critique, And Utilization.
3. Fry, C., & Keith, J. (1986). New methods for old-age research: Strategies for studying diversity. Massachusetts: Bergin & Garvey Publishers, Inc.
4. Glaser, B. G., & Strauss, A. L. (1967). The discovery of grounded theory: Strategies for qualitative research. New York: Aldine.
5. Iran Ministry of Health (2002). National programs of elderly health. Iran, Harayand Pub.