Fels, R. (1966). An introduction to economics: The challenge to the American economy (2nd ed.). Allyn and Bacon.
Chicago-viite (17. p.)Fels, Rendings. An Introduction to Economics: The Challenge to the American Economy. 2nd ed. Boston: Allyn and Bacon, 1966.
MLA-viite (9. p.)Fels, Rendings. An Introduction to Economics: The Challenge to the American Economy. 2nd ed. Allyn and Bacon, 1966.
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