MLA
Wheatley, Phillis. Small Copybook - "Joining Copies". 1754. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 1, Folder 1. https://digital.library.emory.edu/purl/1504xgxdz2-cor.
APA, 6th edition
Wheatley, P. (1754). Small copybook - "Joining Copies" (Box 1, Folder 1) [Manuscripts (document genre)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/1504xgxdz2-cor.
Chicago
Wheatley, Phillis. “Small Copybook - ‘Joining Copies.’” Manuscripts (document genre). Phillis Wheatley Copybooks, 1754. Box 1, Folder 1. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/1504xgxdz2-cor.