MLA
Mowrey, W. H. Sybil Ann Peters Sitting on a Chair Holding Ida Mae on Her Lap, While on a Chair, in Newport, Rhode Island. 1923. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 72. https://digital.library.emory.edu/purl/7719kd51fq-cor.
APA, 6th edition
Mowrey, W. H. (1923). Sybil Ann Peters sitting on a chair holding Ida Mae on her lap, while on a chair, in Newport, Rhode Island (Box 72) [Photographic postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/7719kd51fq-cor.
Chicago
Mowrey, W. H. “Sybil Ann Peters Sitting on a Chair Holding Ida Mae on Her Lap, While on a Chair, in Newport, Rhode Island.” Photographic postcards. Robert Langmuir African American Photograph Collection, 1923. Box 72. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/7719kd51fq-cor.