(2003). Survey research: The basics / Keith F. Punch.
Lua i Stíl Chicago (17ú heag.)Survey Research: The Basics / Keith F. Punch. 2003.
Lua MLA (9ú heag.)Survey Research: The Basics / Keith F. Punch. 2003.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.