MLA
Brown, William C. A Plea for a Thorough Training. [Lincoln University, Pa.?], 0AD. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/627zkh194b-cor.
APA, 6th edition
Brown, W. C. (0 C.E.). A plea for a thorough training [African American author., African American pamphlet., African American publisher.]. [Lincoln University, Pa.?]; Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/627zkh194b-cor.
Chicago
Brown, William C. “A Plea for a Thorough Training.” African American author., African American pamphlet., African American publisher. African American Imprints Collection. [Pennsylvania?]: [Lincoln University, Pa.?], 0AD. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/627zkh194b-cor.