Political Science|Political science (General)|United States Politics & Government 52 Diplomacy & International Relations|International relations|Political Science 19 History|History of North and South America|History: America|Presidential Studies|United States|United States History 10 History|History of North and South America|History: America|United States|United States History 7 History|History of North and South America|History of the Americas|History: America|United States 5 Education|Engineering and Technology|Technology 4 Political Science|United States Politics & Government 4 Bases de datos 3 Ciencias de la salud 3 International relations|Political Science|Political Science & Studies 3 Military and Defense|Military and Naval Science|Military History & Science|Military science|Military science (General) 3 America|History|History of North and South America|History of the Americas|History: America|Indians of North America 2 Civil Rights|Human Rights|Political Science|Political science (General) 2 Civil War period, 1861-1865|History|History of North and South America|History of the Americas|History: America|United States 2 History|History of North and South America|History: America|Twentieth century|United States|United States History 2 Law 2 Medicina 2 Political Science|Political Science & Studies|Political science (General) 2 Publicación en acceso abierto 2 Science|Sciences|Zoology 2 -Historia 1 African American Studies|History|History (General)|History (General) and History of Europe 1 Agricultural education|Agriculture|Agriculture & Farming|Agriculture (General)|Engineering|Engineering (General). Civil engineering (General)|Engineering and Technology|Technology 1 Agriculture|Agriculture (General)|Conservation and Natural Resources|Conservation of natural resources|Environmental Issues|Erosion Control & Soil Conservation|Political Science|Sciences|United States Politics & Government 1 Agriculture|Agriculture (General)|Engineering and Technology|Farm machinery and farm engineering|Technical education. Technical schools|Technology|Technology (General) 1 America|History|History of North and South America|History: America|Indians of North America|United States History 1 Armed Forces|Military and Defense|Military and Naval Science|Military science|Military science (General) 1 Armies: Organization, distribution, military situation|Military and Defense|Military and Naval Science|Military History & Science|Military science 1 Atomic Energy|Atomic physics. Constitution and properties of matter|Energy|Nuclear Power|Physics|Science|Sciences 1 Banking, Finance & Investing|Business and Economics|Business and Economics (General)|Finance|Investment, capital formation, speculation|Social Sciences 1