Case, K. E., Oster, S. E., & Fair, R. C. (2017). Principles of economics (Twelfth edition.). Pearson Education Limited.
Chicago-viite (17. p.)Case, Karl E., Sharon E. Oster, ja Ray C.,Seauthor Fair. Principles of Economics. Twelfth edition. Boston: Pearson Education Limited, 2017.
MLA-viite (9. p.)Case, Karl E., et al. Principles of Economics. Twelfth edition. Pearson Education Limited, 2017.
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