O'BRIEN, F. (1965). Crisis in world communism: Marxism in search in search of efficiency. The free press.
Chicago-viite (17. p.)O'BRIEN, Frank. Crisis in World Communism: Marxism in Search in Search of Efficiency. New york: The free press, 1965.
MLA-viite (9. p.)O'BRIEN, Frank. Crisis in World Communism: Marxism in Search in Search of Efficiency. The free press, 1965.
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