MLA
Musser (Harrisburg, Pa.). Portrait of an African American policeman. unknown. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/156zw3r24f-cor.
APA, 6th edition
Musser (Harrisburg, Pa.). (unknown)[Portrait of an African American policeman]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/156zw3r24f-cor.
Chicago
Musser (Harrisburg, Pa.), Portrait of an African American policeman, unknown, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/156zw3r24f-cor.