20th Corps (XX Corps), Alexander M. McCook, source (link)

20th Corps (McCook's)
The Civil War Archive, Union Corps Histories, "20th Corps (McCook's)." 

[citing "Regimental Losses in the American Civil War (1861-1865)" - William Fox] [The Civil War Archive 1998-2000; page updated 04 Aug. 2001] 
http://web.archive.org/web/20050318195432/
http://www.civilwararchive.com:80/CORPS/20thmcc.htm

Link to source: Alex M. McCook, XX Corp (Twentieth Corps), Union Army

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