See Edwin Bearss' The Campaign for Vicksburg, Vol. II, Grant Strikes a Fatal Blow, Morningside, 1986, Chapter 22, The Struggle for the Bruinsburg Road, pp. 353-372,
The positions of Garrott's 20th at Port Gibson, are found in Warren E. Brabau's Ninethy-Eight Days, A Geographer's View of the Vicksburg Campaign, U of Tenn. Press, 2000, Maps 30-32, The Battle of Port Gibson
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