Rossi, P. H., & Freeman, H. E. (1985). Evaluation: A systematic approach (3rd ed.). Sage.
Lua i Stíl Chicago (17ú heag.)Rossi, Peter H., agus Howard E. Freeman. Evaluation: A Systematic Approach. 3rd ed. Beverly Hills: Sage, 1985.
Lua MLA (8ú heag.)Rossi, Peter H., agus Howard E. Freeman. Evaluation: A Systematic Approach. 3rd ed. Sage, 1985.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.