Chaffee, J. (2015). Thinking critically (Eleventh edition.). Cengage Learning.
Chicago-viite (17. p.)Chaffee, John. Thinking Critically. Eleventh edition. Stamford, Connecticut: Cengage Learning, 2015.
MLA-viite (9. p.)Chaffee, John. Thinking Critically. Eleventh edition. Cengage Learning, 2015.
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