MLA
C. T. Photochrom (Chicago, Ill.). Picking cotton : a group of African American men, an African American woman, an African American boy and African American girl standing in a cotton field [hand colored]. unknown. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4579s4mw94-cor.
APA, 6th edition
C. T. Photochrom (Chicago, Ill.). (unknown)[Picking cotton : a group of African American men, an African American woman, an African American boy and African American girl standing in a cotton field [hand colored]]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4579s4mw94-cor.
Chicago
C. T. Photochrom (Chicago, Ill.), Picking cotton : a group of African American men, an African American woman, an African American boy and African American girl standing in a cotton field [hand colored], unknown, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4579s4mw94-cor.