History 277 Fire fighters 269 World War, 1939-1945 92 Police 89 HISTORY 81 Law and legislation 80 Fighter planes 65 General 63 Legal status, laws, etc 58 Armed Forces 53 Salaries, etc 52 Procurement 50 Politics and government 48 Fighter pilots 41 POLITICAL SCIENCE 39 Officials and employees 37 SOCIAL SCIENCE 34 Aerial operations, American 31 Appropriations and expenditures 29 Histoire 28 Social conditions 28 Pensions 27 BIOGRAPHY & AUTOBIOGRAPHY 25 Defense contracts 25 Training of 25 Military operations, Aerial 24 Political aspects 24 Campaigns 23 Design and construction 23 Costs 22