Babbie, E. (1998). The practice of social research (8th.ed.). Wadsworth.
Lua i Stíl Chicago (17ú heag.)Babbie, Earl. The Practice of Social Research. 8th.ed. Belmont: Wadsworth, 1998.
Lua MLA (9ú heag.)Babbie, Earl. The Practice of Social Research. 8th.ed. Wadsworth, 1998.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.