BABBIE, E. (1989). The Practice Of Social Research Earl Babbie. Wadsworth Publishing.
Lua i Stíl Chicago (17ú heag.)BABBIE, Earl. The Practice Of Social Research Earl Babbie. Wadsworth Publishing, 1989.
Lua MLA (8ú heag.)BABBIE, Earl. The Practice Of Social Research Earl Babbie. Wadsworth Publishing, 1989.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.