- Islandora Repository
- Mss.B.B61_K
- Keppel, Frederick P.: To Boas. 1906 Sept. 5
- Keppel, Frederick P.: To Boas. 1907 Sept. 28
- Keppel, Frederick P.: To Boas. 1908 Oct. 14
- Keppel, Frederick P.: To Boas. 1908 Sept. 21
- Keppel, Frederick P.: To Boas. 1909 Feb. 9
- Keppel, Frederick P.: To Boas. 1909 July 1
- Keppel, Frederick P.: To Boas. 1909 July 15
- Keppel, Frederick P.: To Boas. 1909 July 6
- Keppel, Frederick P.: To Boas. 1909 July 6
- Keppel, Frederick P.: To Boas. 1909 Mar. 13
- Keppel, Frederick P.: To Boas. 1909 Mar. 22
- Keppel, Frederick P.: To Boas. 1909 Sept. 20
