MLA
Union Patriotic Envelope - "'The Star-Spangled Banner in Triumph Shall Wave, O'Er the Land of the Free and the Home of the Brave.' 'The Federal Union-It Must and Shall Be Preserved' - Andrew Jackson. ' If Anyone Attempts to Haul down the American Flag, Shoot Him on the Spot.' - John A. Dix. 1861. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 21, Folder 7. https://digital.library.emory.edu/purl/337vmcvfw9-cor.
APA, 6th edition
Union patriotic envelope - "'The star-spangled banner in triumph shall wave, O'er the land of the free and the home of the brave.' 'The Federal Union-it must and shall be preserved' - Andrew Jackson. ' If anyone attempts to haul down the American Flag, shoot him on the spot.' - John A. Dix. (Box 21, Folder 7). (1861). [Envelopes]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/337vmcvfw9-cor.
Chicago
“Union Patriotic Envelope - "'The Star-Spangled Banner in Triumph Shall Wave, O'Er the Land of the Free and the Home of the Brave.' 'The Federal Union-It Must and Shall Be Preserved' - Andrew Jackson. ' If Anyone Attempts to Haul down the American Flag, Shoot Him on the Spot.' - John A. Dix.” Envelopes. Civil War Collection, 1861. Box 21, Folder 7. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/337vmcvfw9-cor.