MLA
Artvue Post Card Co. (New York, N.Y.). Boys and girls entering a building at Ashford Hills Camp, in Scarsdale, New York. unknown. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/474cnp5hth-cor.
APA, 6th edition
Artvue Post Card Co. (New York, N.Y.). (unknown)[Boys and girls entering a building at Ashford Hills Camp, in Scarsdale, New York]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/474cnp5hth-cor.
Chicago
Artvue Post Card Co. (New York, N.Y.), Boys and girls entering a building at Ashford Hills Camp, in Scarsdale, New York, unknown, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/474cnp5hth-cor.