MLA
Letter from an Unidentified Person to Thomas L. Douglass. Pitts Theology Library, Box 1, Folder 23. https://digital.library.emory.edu/purl/692t4b8j1d-cor.
APA, 6th edition
Letter from an unidentified person to Thomas L. Douglass (Box 1, Folder 23). [Letters (correspondence)]. Pitts Theology Library. https://digital.library.emory.edu/purl/692t4b8j1d-cor.
Chicago
“Letter from an Unidentified Person to Thomas L. Douglass.” Letters (correspondence). Robert Paine Papers, 1828-1882, n.d. Box 1, Folder 23. Pitts Theology Library. https://digital.library.emory.edu/purl/692t4b8j1d-cor.