MLA
Krebbs, S. H., and Co. A. & M. College for Colored People in Greensboro, N.C. 1913. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 69. https://digital.library.emory.edu/purl/013mw6m939-cor.
APA, 6th edition
Krebbs, S. H., & C. (1913). A. & M. College for Colored People in Greensboro, N.C. (Box 69) [Postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/013mw6m939-cor.
Chicago
Krebbs, S. H., and Co. “A. & M. College for Colored People in Greensboro, N.C.” Postcards. Robert Langmuir African American Photograph Collection, 1913. Box 69. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/013mw6m939-cor.