MLA
Lions., Three. Come to Sunday School, You'Ll Hear Stories from the Bible in Sunday School. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 74. https://digital.library.emory.edu/purl/494vhhmgt5-cor.
APA, 6th edition
Lions., T. Come to Sunday school, you'll hear stories from the Bible in Sunday school (Box 74) [Postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/494vhhmgt5-cor.
Chicago
Lions., Three. “Come to Sunday School, You'Ll Hear Stories from the Bible in Sunday School.” Postcards. Robert Langmuir African American Photograph Collection, n.d. Box 74. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/494vhhmgt5-cor.