MLA
Riddick, Lavina. Letter from Lavina Riddick[?] to Her Husband, Elbert Riddick. Elbert Riddick Served in Company C of the 19th North Carolina Infantry Regiment. - April 1 [No Year] (Photocopy). 1861. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 10, Folder 1. https://digital.library.emory.edu/purl/972p5hqd21-cor.
APA, 6th edition
Riddick, L. (1861). Letter from Lavina Riddick[?] to her husband, Elbert Riddick. Elbert Riddick served in Company C of the 19th North Carolina Infantry Regiment. - April 1 [No Year] (photocopy) (Box 10, Folder 1) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/972p5hqd21-cor.
Chicago
Riddick, Lavina. “Letter from Lavina Riddick[?] to Her Husband, Elbert Riddick. Elbert Riddick Served in Company C of the 19th North Carolina Infantry Regiment. - April 1 [No Year] (Photocopy).” Letters (correspondence). Civil War Collection, 1861. Box 10, Folder 1. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/972p5hqd21-cor.