1. Patton, M. Q. 1997.Utilization-Focused evaluation. The New Century Text,, 3rd, xivThousand Oaks, CA: Sage Publications.
2. Rossi, P. H., Freeman, H. E. and Lipsey, M. W. 1999.Evaluation: A systematic approach, 6th, 55Thousand Oaks, CA: Sage Publications.