31 jul 2000 año - Sources

Descripción:

http://www.abrahamlincolnonline.org/lincoln/speeches/gettysburg.htm

http://www.history.com/topics/american-civil-war/battle-of-gettysburg

https://www.civilwar.org/learn/civil-war/battles/antietam

https://www.usnews.com/news/articles/2008/07/23/abraham-lincoln-and-the-election-of-1860

https://en.wikipedia.org/wiki/Battle_of_Gettysburg

https://www.thinglink.com/scene/702902291958595584

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