Richberg, D. R. (1957). Labor union monopoly: A clear and present danger / by Donald R. Richberg (2. print.). Regnery.
Chicago-viite (17. p.)Richberg, Donald Randall. Labor Union Monopoly: A Clear and Present Danger / by Donald R. Richberg. 2. print. Chicago: Regnery, 1957.
MLA-viite (8. p.)Richberg, Donald Randall. Labor Union Monopoly: A Clear and Present Danger / by Donald R. Richberg. 2. print. Regnery, 1957.
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