United States. Interstate Commerce Commission. (1939). A Statistical Analysis of Carriers' Monthly Hours of Service Reports, For the Year Ended June 30, 1939. [s.n.].
Chicago Style (17th ed.) CitationUnited States. Interstate Commerce Commission. A Statistical Analysis of Carriers' Monthly Hours of Service Reports, For the Year Ended June 30, 1939. [Washington]: [s.n.], 1939.
MLA (9th ed.) CitationUnited States. Interstate Commerce Commission. A Statistical Analysis of Carriers' Monthly Hours of Service Reports, For the Year Ended June 30, 1939. [s.n.], 1939.
Warning: These citations may not always be 100% accurate.