APA (7th ed.) Zitazioa
United States Department of Labor. (1958). Directory of labor organizations. United States Department of Labor.
Chicago Style (17th ed.) Zitazioa
United States Department of Labor. Directory of Labor Organizations. Washington: United States Department of Labor, 1958.
MLA (9th ed.) Zitazioa
United States Department of Labor. Directory of Labor Organizations. United States Department of Labor, 1958.
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