| HH 5.1 | Land and Facilities Development Administration (1965-1969) |
| SB 8.1 | Law Bureau (1916-1919) |
| LC 10.1 | Law Library (1905-1981) |
| LC 42.1 | Law Library (1981- ) |
| S 7.2 | Laws of the United States |
| D 108.101 | Legal Services Agency (1978-?) |
| T 23.1 | Library (1818-?) |
| J 4.1 | Library (1873-?) |
| W 11.1 | Library (1880-1908) |
| LC 8.1 | Library Buildings and Grounds Superintendent (1897-1922) |
| LC 1.1 | Library of Congress (1800- ) |
| LC 30.1 | Library Services (1940- ) |
| T 24.1 | Life-Saving Service (1878-1915) |
| T 25.1 | Lighthouse Board (1852-1903) |
