United States. War Department. Office of the Chief of Engineers. [Front Cover: Military Maps illustrating the Operations of the Armies of the Potomac & James, May 4th 1864 to April 9th 1865], text, 1869; (https://texashistory.unt.edu/ark:/67531/metapth193417/m1/1/: accessed August 15, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .