Subject
National security
8
History
7
Military art and science
7
Public health
7
Aids to navigation
6
Notices to mariners
6
Pilot guides
6
Aeronautics Safety measures
5
Agriculture Economic aspects
5
National parks and reserves
5
Power resources
5
Safety measures
5
Aviation
4
Diplomatic and consular service, American
4
Forest management
4
Research
4
Security, International
4
Tax administration and procedure
4
Taxation Law and legislation
4
United States
4
AIDS (Disease) Prevention
3
Aeronautics
3
Agriculture
3
Arts
3
Banks and banking
3
Conservation of natural resources
3
Fisheries
3
Forest fires Prevention and control
3
Hijacking of ships
3
Intelligence service
3
Meteorological services
3
Meteorological services Employees
3
Military history
3
Officials and employees
3
Pedestrians Safety measures
3
Piracy
3
Prices
3
Produce trade
3
Social security
3
Veterans Medical care
3
Wetland conservation
3
Administrative remedies
2
Agriculture Research
2
Airplanes, Military Maintenance and repair
2
Appropriations and expenditures
2
Archives
2
Artillery, Field and mountain
2
Atmospheric temperature States
2
Aviation mechanics
2
Buildings Energy conservation
2
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