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- A.C.L. Gatewood Papers, 1801/19191
- Abner Osburn, Physician, Papers, 1846/19011
- Adolphus P. Howard Papers, 1850/19381
- Aileen Shafer, Collector, Material regarding African-Americans, 1829/18845
- Alfred Beckley (1802-1888) Papers, 1832/18561
- Alfred Hughes Stock Certificates and Receipts, 1852/18651
- Allen Family Papers, 1766/193330
- Alpheus Garrison Civil War Records, 1804/18881
- Alston Gordon Dayton Papers, 1846/19392
- Ambrotype Portrait Photograph of Mrs. Josephine Neal Robb in Case, 1850/18701
- American Missionary Society Papers, 1848/18821
- Ancella Bickley, Historian, Research Papers regarding African-Americans, 1775/2018, bulk 1970/201125
- Andrew Delmar Hopkins Papers, 1787/19431
- Andrew S. Core, Typescripts and Charts, 1804/18881