MLA
Jenkins, S. W. Letter from S. W. Jenkins to Susan A. Kenny. Jenkins Served in the 9th, Then 58th Alabama Infantry Regiment - November 13, 1863. 1863. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 4, Folder 28. https://digital.library.emory.edu/purl/81289320fq-cor.
APA, 6th edition
Jenkins, S. W. (1863). Letter from S. W. Jenkins to Susan A. Kenny. Jenkins served in the 9th, then 58th Alabama Infantry Regiment - November 13, 1863 (Box 4, Folder 28) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/81289320fq-cor.
Chicago
Jenkins, S. W. “Letter from S. W. Jenkins to Susan A. Kenny. Jenkins Served in the 9th, Then 58th Alabama Infantry Regiment - November 13, 1863.” Letters (correspondence). Civil War Collection, 1863. Box 4, Folder 28. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/81289320fq-cor.