MLA
Dormand Post Card, Riverhead (Long Island, N.Y.). Ninety-nine steps is a famous street in St. Thomas, Virgin Islands, U.S.A. : with a man walking down the steps. June 1, 1966. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4300zpc86v-cor.
APA, 6th edition
Dormand Post Card, Riverhead (Long Island, N.Y.). (June 1, 1966)[ Ninety-nine steps is a famous street in St. Thomas, Virgin Islands, U.S.A. : with a man walking down the steps]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4300zpc86v-cor.
Chicago
Dormand Post Card, Riverhead (Long Island, N.Y.), Ninety-nine steps is a famous street in St. Thomas, Virgin Islands, U.S.A. : with a man walking down the steps, June 1, 1966, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4300zpc86v-cor.