Swokowski, E. W. (2012). Precalculus: Functions and graphs (Twelfth edition.). Brooks/Cole Cengage Learning.
Chicago-viite (17. p.)Swokowski, Earl W. Precalculus: Functions and Graphs. Twelfth edition. Australia: Brooks/Cole Cengage Learning, 2012.
MLA-viite (9. p.)Swokowski, Earl W. Precalculus: Functions and Graphs. Twelfth edition. Brooks/Cole Cengage Learning, 2012.
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