FRANK, R. H. (2013). Principles of Economics 5th ed. Mc GrawHill.
Lua i Stíl Chicago (17ú heag.)FRANK, Robert H. Principles of Economics 5th Ed. Mc GrawHill, 2013.
Lua MLA (8ú heag.)FRANK, Robert H. Principles of Economics 5th Ed. Mc GrawHill, 2013.
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