Hawley, E. W. (1981). Herbert Hoover as secretary of commerce: Studies in New Era thought and practice. University of Iowa.
Παραπομπή σε μορφή Chicago (17η εκδ.)Hawley, Elis W. Herbert Hoover as Secretary of Commerce: Studies in New Era Thought and Practice. IOWA: University of Iowa, 1981.
Παραπομπή σε μορφή MLA (9th εκδ.)Hawley, Elis W. Herbert Hoover as Secretary of Commerce: Studies in New Era Thought and Practice. University of Iowa, 1981.
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