MLA
Rich, Richard H., 1901-1975. Letter from Richard H. Rich, President of Rich's department stores, to Jessie O. Thomas, President of the Atlanta Chapter of The Frontiers of America, Inc., responding to the first letter of Jessie O. Thomas, expressing regret that he cannot meet with Mary Louise Allan due to conflicting schedules - June 28, 1960. June 28, 1960. Richard H. Rich Papers, 1902-1981. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/105s7h44zp-cor.
APA, 6th edition
Rich, Richard H., 1901-1975. (June 28, 1960)[Letter from Richard H. Rich, President of Rich's department stores, to Jessie O. Thomas, President of the Atlanta Chapter of The Frontiers of America, Inc., responding to the first letter of Jessie O. Thomas, expressing regret that he cannot meet with Mary Louise Allan due to conflicting schedules - June 28, 1960]. Richard H. Rich Papers, 1902-1981, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/105s7h44zp-cor.
Chicago
Rich, Richard H., 1901-1975, Letter from Richard H. Rich, President of Rich's department stores, to Jessie O. Thomas, President of the Atlanta Chapter of The Frontiers of America, Inc., responding to the first letter of Jessie O. Thomas, expressing regret that he cannot meet with Mary Louise Allan due to conflicting schedules - June 28, 1960, June 28, 1960, Richard H. Rich Papers, 1902-1981, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/105s7h44zp-cor.