Map of the Battle Fields of Manassas and the Surrounding Region Showing the Various Actions of the 21st July 1861, Between the Armies of the Confederate States and the United States. Surveyed and Drawn by W. G. Atkinson, Acting 1st Lieu't., Engineers...Headquarters, 1st Corps, Army of Potomac [Confederate], Manassas Junction, August 1861.

Chicago citation style
War Department. Office of the Chief of Engineers. 1818-9/18/1947. Map of the Battle Fields of Manassas and the Surrounding Region Showing the Various Actions of the 21st July 1861, Between the Armies of the Confederate States and the United States. Surveyed and Drawn by W. G. Atkinson, Acting 1st Lieu't., Engineers...Headquarters, 1st Corps, Army of Potomac [Confederate], Manassas Junction, August 1861.. 1861-08. Retrieved from the Digital Public Library of America, http://catalog.archives.gov/id/305595. (Accessed June 22, 2018.)
APA citation style
War Department. Office of the Chief of Engineers. 1818-9/18/1947, (1861-08) Map of the Battle Fields of Manassas and the Surrounding Region Showing the Various Actions of the 21st July 1861, Between the Armies of the Confederate States and the United States. Surveyed and Drawn by W. G. Atkinson, Acting 1st Lieu't., Engineers...Headquarters, 1st Corps, Army of Potomac [Confederate], Manassas Junction, August 1861.. Retrieved from the Digital Public Library of America, http://catalog.archives.gov/id/305595
MLA citation style
War Department. Office of the Chief of Engineers. 1818-9/18/1947. Retrieved from the Digital Public Library of America <http://catalog.archives.gov/id/305595>.
Note: These citations are programmatically generated and may be incomplete.