Babbie, E. (2010). The practice of social research (Twelfth edition.). Wadsworth Cengage Learning.
Cita Chicago (17th ed.)Babbie, Earl. The Practice of Social Research. Twelfth edition. Belmont, CA: Wadsworth Cengage Learning, 2010.
Cita MLA (9th ed.)Babbie, Earl. The Practice of Social Research. Twelfth edition. Wadsworth Cengage Learning, 2010.
Atenció: Aquestes cites poden no estar 100% correctes.