Wilkinson, D., & Birmingham, P. (2003). Using research instruments: A guide for researchers. RoutledgeFalmer.
Lua i Stíl Chicago (17ú heag.)Wilkinson, David, agus Peter Birmingham. Using Research Instruments: A Guide for Researchers. London: RoutledgeFalmer, 2003.
Lua MLA (9ú heag.)Wilkinson, David, agus Peter Birmingham. Using Research Instruments: A Guide for Researchers. RoutledgeFalmer, 2003.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.