MLA
McNeill, Robert H, McNeill News Photo Service (Washington, D.C.. Men and women in cap and gowns on graduation day. 1920. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/006sxksn57-cor.
APA, 6th edition
McNeill, Robert H, & McNeill News Photo Service (Washington, D.C.. (1920)[Men and women in cap and gowns on graduation day]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/006sxksn57-cor.
Chicago
McNeill, Robert H, McNeill News Photo Service (Washington, D.C., Men and women in cap and gowns on graduation day, 1920, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/006sxksn57-cor.