Creswell, J. W. (2009). Research Design. Response Books.
Lua i Stíl Chicago (17ú heag.)Creswell, John W. Research Design. New Delhi: Response Books, 2009.
Lua MLA (9ú heag.)Creswell, John W. Research Design. Response Books, 2009.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.