United States. Aeronautical Chart Service. (1947). Isobars and prevailing winds chart, July: Northern Hemisphere (Advance edition.). U.S. Army Air Forces.
Chicago Style (17th ed.) CitationUnited States. Aeronautical Chart Service. Isobars and Prevailing Winds Chart, July: Northern Hemisphere. Advance edition. [Washington, D.C.]: U.S. Army Air Forces, 1947.
MLA (9th ed.) CitationUnited States. Aeronautical Chart Service. Isobars and Prevailing Winds Chart, July: Northern Hemisphere. Advance edition. U.S. Army Air Forces, 1947.
Warning: These citations may not always be 100% accurate.