MLA
Gardner, Alexander, 1821-1882. Abraham Lincoln, 16th president of the United States (8'' x 10'' reproduction). April 10, 1865. Civil War Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/897kprr62n-cor.
APA, 6th edition
Gardner, Alexander, 1821-1882. (April 10, 1865)[Abraham Lincoln, 16th president of the United States (8'' x 10'' reproduction)]. Civil War Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/897kprr62n-cor.
Chicago
Gardner, Alexander, 1821-1882, Abraham Lincoln, 16th president of the United States (8'' x 10'' reproduction), April 10, 1865, Civil War Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/897kprr62n-cor.