- N. B. White Letter to Darius White, 18621
- N. Cairns Letter to Hugh McCalmont, 18312
- N. Chester Sorensen Letter to Frank Lloyd Wright, 19421
- N. F. McNorton Record of Whiskey Dispensed, 1928/19321
- N. J. Pittman Account Book, 1855/18811
- N. L. Michael Letters, 1967/19682
- N. S. Andrews Letter, 18641
- N.R.A. Roller Hockey Club (Allentown, Pa.) Minutes, 19342
- NASA Collection, 1988/1994, bulk 199310
- Nack, Kenneth. Artist file: miscellaneous uncatalogued material1
- Nadar, Félix, 1820-1910. Artist file: miscellaneous uncatalogued material1
- Nadelman, Elie, 1882-1946. Artist file: miscellaneous uncatalogued material1
- Nadler, Harry, 1930-1990. Artist file: miscellaneous uncatalogued material1
- Nagano, Shozo. Artist file: miscellaneous uncatalogued material1
- Nagare, Masayuki, 1923-. Artist file: miscellaneous uncatalogued material1