See related link 'Wikipedia - US Army Regimental System'

U S Army colors

George J. Shively has written:

'Record of S. S. U. 585' -- subject(s): United States, World War, 1914-1918, United States. Army. Ambulance Service. Section, 585th, Regimental histories

George Brinton McClellan has written:

'Regulations and Instructions for the Field Service of the U. S. Cavalry in Time of War: To which ..'

'The Army of the Potomac' -- subject(s): Campaigns, United States, Regimental histories, United States. Army of the Potomac, History

'McClellans' own story'

Army Regulation 600-82