MLA
Spencer, Thomas. Historical Marker in Coweta County, Georgia Showing the Birthplace of William Thomas Overby, a Confederate Soldier Who Refused to Reveal Location of His Battalion When Captured and Was Executed Because of It. 1958. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 15, Folder 1. https://digital.library.emory.edu/purl/965v6wwr2c-cor.
APA, 6th edition
Spencer, T. (1958). Historical marker in Coweta County, Georgia showing the birthplace of William Thomas Overby, a Confederate soldier who refused to reveal location of his battalion when captured and was executed because of it (Box 15, Folder 1) [Black-and-white photographs]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/965v6wwr2c-cor.
Chicago
Spencer, Thomas. “Historical Marker in Coweta County, Georgia Showing the Birthplace of William Thomas Overby, a Confederate Soldier Who Refused to Reveal Location of His Battalion When Captured and Was Executed Because of It.” Black-and-white photographs. Civil War Collection, 1958. Box 15, Folder 1. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/965v6wwr2c-cor.