Piotrowski, R. (1978). Cartels and trusts: Their origin and historical development from the economic and legal aspects. Porcupine Press.
Chicago-viite (17. p.)Piotrowski, Roman. Cartels and Trusts: Their Origin and Historical Development from the Economic and Legal Aspects. Philadelphia: Porcupine Press, 1978.
MLA-viite (9. p.)Piotrowski, Roman. Cartels and Trusts: Their Origin and Historical Development from the Economic and Legal Aspects. Porcupine Press, 1978.
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