MLA
Cook, James, Jr. Fraternity Candidates - Sigma Nu Costume Party. 1949. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 17, Folder 1. https://digital.library.emory.edu/purl/969866t293-cor.
APA, 6th edition
Cook, J., Jr. (1949). Fraternity Candidates - Sigma Nu costume party (Box 17, Folder 1) [Black-and-white photographs]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/969866t293-cor.
Chicago
Cook, James, Jr. “Fraternity Candidates - Sigma Nu Costume Party.” Black-and-white photographs. EU Office of Alumni Publications Photos Deposit Collection 1, 1949. Box 17, Folder 1. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/969866t293-cor.