History 573 Museums 345 Mathematical models 259 Politics and government 243 Armed Forces 208 Periodicals 185 Law and legislation 162 hơn ... Study and teaching 159 Humanities 152 History and criticism 139 International relations 132 Philosophy 128 Research 128 Data processing 127 Learning and scholarship 127 Encyclopedias and dictionaries 119 Social aspects 115 Foreign relations 114 Education 110 Art 108 Military policy 107 Attorneys general's opinions 102 Civilization 95 Science 94 Evaluation 93 Management 92 Intellectual life 90 Economic conditions 89 Economic aspects 84 Museum techniques 83 ít hơn ...