MLA
De Youngs' (N.Y.). A portrait of Wm. P. Laurence. unknown. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/556931zcvj-cor.
APA, 6th edition
De Youngs' (N.Y.). (unknown)[A portrait of Wm. P. Laurence]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/556931zcvj-cor.
Chicago
De Youngs' (N.Y.), A portrait of Wm. P. Laurence, unknown, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/556931zcvj-cor.