SPENCER, D. E. (1990). Studi guide parkin economics. Addison-Wesley Pub.
Cita Chicago Style (17a ed.)SPENCER, David E. Studi Guide Parkin Economics. Reading: Addison-Wesley Pub, 1990.
Cita MLA (9a ed.)SPENCER, David E. Studi Guide Parkin Economics. Addison-Wesley Pub, 1990.
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