Borchard, G. A. (2011). Abraham Lincoln and Horace Greeley. Southern Illinois University Press.
Lua i Stíl Chicago (17ú heag.)Borchard, Gregory A. Abraham Lincoln and Horace Greeley. Carbondale: Southern Illinois University Press, 2011.
Lua MLA (9ú heag.)Borchard, Gregory A. Abraham Lincoln and Horace Greeley. Southern Illinois University Press, 2011.
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