| Circular letter, on Dr. Jewett's removal to Cesarea | Amerikan Bord Heyeti (American Board) | 1855 |
| Letter sent by [J.E. Pierce] from London to the American Board in Constantinople on his journey to Constantinople | Amerikan Bord Heyeti (American Board) | 1878-09-24 |
| Letter, extracts of the S.B. Bergne's letter to B. Barker | Amerikan Bord Heyeti (American Board) | 1854-07-25 |
 | Letter, regarding application to the Committee ad Interim, to Tillman C. Trowbridge | Amerikan Bord Heyeti (American Board) | 1860 |
| Letter, to Charles T. Riggs, from ? | Amerikan Bord Heyeti (American Board) | 1911-02-06 |
| Letter, to Charles T. Riggs, from A.R. Hoover | Amerikan Bord Heyeti (American Board) | 1911-02 |
 | Letter, to Charles T. Riggs, from A.R. Hoover | Amerikan Bord Heyeti (American Board) | 1912-07-22 |
 | Letter, to Charles T. Riggs, from A.T. Daghlian, Anatolia College | Amerikan Bord Heyeti (American Board) | 1912-05-01 |
| Letter, to Charles T. Riggs, from A.T. Daghlian, Anatolia College | Amerikan Bord Heyeti (American Board) | 1912-01-20 |
| Letter, to Charles T. Riggs, from A.T. Daghlian, Anatolia College | Amerikan Bord Heyeti (American Board) | 1912-01-03 |
 | Letter, to Charles T. Riggs, from Charles C. Tracy, Anatolia College | Amerikan Bord Heyeti (American Board) | 1912-05-22 |
| Letter, to Charles T. Riggs, from Charlette R. Willard | Amerikan Bord Heyeti (American Board) | 1913-01-25 |
 | Letter, to Charles T. Riggs, from Charlotte R. Willard | Amerikan Bord Heyeti (American Board) | 1912-04-20 |
 | Letter, to Charles T. Riggs, from Edward F. Carey | Amerikan Bord Heyeti (American Board) | 1912-05-08 |
 | Letter, to Charles T. Riggs, from Edward Riggs | Amerikan Bord Heyeti (American Board) | 1912-02-02 |
 | Letter, to Charles T. Riggs, from Ernest C. Partridge | Amerikan Bord Heyeti (American Board) | 1912-04-18 |
 | Letter, to Charles T. Riggs, from Ernest C. Partridge | Amerikan Bord Heyeti (American Board) | 1913-05-10 |
 | Letter, to Charles T. Riggs, from Ernest C. Partridge | Amerikan Bord Heyeti (American Board) | 1913-02-28 |
 | Letter, to Charles T. Riggs, from Ernest C. Partridge | Amerikan Bord Heyeti (American Board) | 1912-07-13 |
 | Letter, to Charles T. Riggs, from Ernest C. Partridge | Amerikan Bord Heyeti (American Board) | 1912-02-03 |
