STILWELL, J. (1975). Workbook to accompany the fourth edition of an introduction to positive economics. E.L.B.S., Weidenfeld and Nicolson.
Chicago-viite (17. p.)STILWELL, J.A. Workbook to Accompany the Fourth Edition of an Introduction to Positive Economics. London: E.L.B.S., Weidenfeld and Nicolson, 1975.
MLA-viite (9. p.)STILWELL, J.A. Workbook to Accompany the Fourth Edition of an Introduction to Positive Economics. E.L.B.S., Weidenfeld and Nicolson, 1975.
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