Further information: Organization of the forces operating against Richmond, on the morning of May 5, 1864: Official Records, Series I, Volume XXXVI, Part 1, pages 106–116; Organization of Army of the Potomac, May 31, 1864: Official Records, Series I, Volume XXXVI, Part 1, pages 198–209.
This Army Corps was under direct orders of Lieut. Gen. Ulysses S. Grant until May 24, 1864, when it was assigned to the Army of the Potomac. See: Official Records, Series I, Volume XXXVI, Part 1, page 113 (note at the bottom of the page).
June 2–15, 1864: temporarily attached to the Army of the Potomac from the Army of the James (and engaged at Cold Harbor only). See: Official Records, Series I, Volume XXXVI, Part 1, page 178 (note at the bottom of the page).
Further information: Army of the James (in the field), on the morning of May 5, 1864: Official Records, Series I, Volume XXXVI, Part 1, pages 116–119.
"Present for duty" (April 30, 1864): Army of the Potomac: 102,869; IX Army Corps: 21,363. See Abstract from tri-monthly return of the Army of the Potomac, Maj. Gen. George G. Meade, U.S. Army commanding, April 30, 1864 (Official Records, Series I, Volume XXXVI, Part 1, page 198) and Abstract from return of the Ninth Army Corps, commanded by Maj. Gen. Ambrose E. Burnside, U.S. Army, for April 30, 1864 (Official Records, Series I, Volume XXXVI, Part 1, page 915).
General summary from the Rapidan to the James River, May 5 – June 24, 1864: Official Records, Series I, Volume XXXVI, Part 1, page 188.
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Field return of the Army of the Potomac for June 1, 1864 (Official Records, Series I, Volume XXXVI, Part 1, page 209).