MLA
Hugh C. Leighton Co., Manufacturers (Portland, Me.). A bunch of coons : four African American boys sitting in the grass [hand colored]. unknown. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/252j6q575g-cor.
APA, 6th edition
Hugh C. Leighton Co., Manufacturers (Portland, Me.). (unknown)[A bunch of coons : four African American boys sitting in the grass [hand colored]]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/252j6q575g-cor.
Chicago
Hugh C. Leighton Co., Manufacturers (Portland, Me.), A bunch of coons : four African American boys sitting in the grass [hand colored], unknown, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/252j6q575g-cor.