MLA
Empire (N.Y.). Portrait of Lewis, an African American man. unknown. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/044bnzs7p8-cor.
APA, 6th edition
Empire (N.Y.). (unknown)[Portrait of Lewis, an African American man]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/044bnzs7p8-cor.
Chicago
Empire (N.Y.), Portrait of Lewis, an African American man, unknown, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/044bnzs7p8-cor.