| SuDoc Classification System |
| A |
Agriculture Department |
| AE |
National Archives and Records Administration |
| C |
Commerce Department |
| CC |
Federal Communications Commission |
| CR |
Civil Rights Commission |
| D |
Defense Department |
| E |
Energy Department |
| ED |
Education Department |
| EP |
Environmental Protection Agency |
| FEM |
Federal Emergency Management Agency |
| FT |
Federal Trade Commission |
| GA |
General Accounting Office |
| GP |
Government Printing Office |
| GS |
General Services Administration |
| HE |
Health and Human Services Department |
| HH |
Housing and Urban Development Department |
| I |
Interior Department |
| IC |
Interstate Commerce Commission |
| J |
Justice Department |
| JU |
Judiciary |
| L |
Labor Department |
| LC |
Library of Congress |
| NAS |
National Aeronautics and Space Administration |
| NF |
National Foundation on the Arts and the Humanities |
| NS |
National Science Foundation |
| P |
United States Postal Service |
| PR |
President of the United States |
| PREX |
Executive Office of the President |
| S |
State Department |
| SE |
Securities and Exchange Commission |
| SI |
Smithsonian Institution |
| SSA |
Social Security Administration |
| T |
Treasury Department |
| TD |
Transportation Department |
| VA |
Veteran Affairs Department |
| X, Y |
Congress |
| Y 3 |
Congressional Committees |
