Babbie, E. (1989). The practice of social research (5th.ed.). Wadsworth.
Chicago-čujuhus (17. p.)Babbie, Earl. The Practice of Social Research. 5th.ed. Belmont: Wadsworth, 1989.
MLA-čujuhus (9. p.)Babbie, Earl. The Practice of Social Research. 5th.ed. Wadsworth, 1989.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.