MLA
Co., E. C. Kropp. Two Jacks and a Jill-down in Sunny Dixie. 1937. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 72. https://digital.library.emory.edu/purl/713905qfwp-cor.
APA, 6th edition
Co., E. C. K. (1937). Two Jacks and a Jill-down in sunny Dixie (Box 72) [Postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/713905qfwp-cor.
Chicago
Co., E. C. Kropp. “Two Jacks and a Jill-down in Sunny Dixie.” Postcards. Robert Langmuir African American Photograph Collection, 1937. Box 72. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/713905qfwp-cor.