MLA
Brown, and Ryan. Union Patriotic Envelopes Dealing with Secession - "This Modern Blondin Leaves but One Impression / Upon the Mind of Every Calm Spectator: How Easily We Circumvent SECESSION / Must Now He Clearly Seen by This Arch-Traitor." Published by Brown & Ryan, New York. Brown & Ryan, 1861. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 21, Folder 8. https://digital.library.emory.edu/purl/211kh18b8b-cor.
APA, 6th edition
B., & R. (1861). Union patriotic envelopes dealing with secession - "This modern Blondin leaves but one impression / Upon the mind of every calm spectator: How easily we circumvent SECESSION / Must now he clearly seen by this arch-traitor." Published by Brown & Ryan, New York (Box 21, Folder 8) [Envelopes]. Brown & Ryan; Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/211kh18b8b-cor.
Chicago
Brown, and Ryan. “Union Patriotic Envelopes Dealing with Secession - ‘This Modern Blondin Leaves but One Impression / Upon the Mind of Every Calm Spectator: How Easily We Circumvent SECESSION / Must Now He Clearly Seen by This Arch-Traitor." Published by Brown & Ryan, New York.” Envelopes. Civil War Collection. New York City, NY: Brown & Ryan, 1861. Box 21, Folder 8. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/211kh18b8b-cor.