Beard, C. A. (1939). America in midpassage, by Charles A. Beard & Mary R. Beard; illustrated from drawings by Wilfred Jones. Macmillan.
Lua i Stíl Chicago (17ú heag.)Beard, Charles A. America in Midpassage, by Charles A. Beard & Mary R. Beard; Illustrated from Drawings by Wilfred Jones. New York: Macmillan, 1939.
Lua MLA (9ú heag.)Beard, Charles A. America in Midpassage, by Charles A. Beard & Mary R. Beard; Illustrated from Drawings by Wilfred Jones. Macmillan, 1939.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.