- Ilionardo, Pasco (1)
- Illian, George, 1894-1932 (5)
- Illinois Commerce Commission (1)
- Illinois State Geological Survey (4)
- Illinois. Railroad and Warehouse Commission. (2)
- Ilsley, George F (1)
- Imai, Kosuke (Princeton University) (1)
- Imhof, O. Steward (1)
- Imhoff (1)
- Imkeller, Peter (Humboldt-Universität) (1)
- Immerman (1)
- Immerman, Bob (4)
- Immerman, Robert (1)
- Imperatorskai︠a︡ akademīi︠a︡ nauk i khudozhestv (Russia) (1)
- Imprimerie Grou-Radenez (1)
- Imrie, William F. (1)
- Ina Liljegvist & Co (1)
- Independent Publishing Co. (Grand Island, Neb.) (1)
- India. Army. Simla Army. Quartermaster-General's Office. (1)
- India. Information Services (1)
