Universities and colleges 65,813 Urbanization 24,068 Underground movements 23,923 Unemployment 20,371 Urban renewal 16,988 Unemployed 12,824 U.S. states 10,363 Utopias 9,551 Unemployment insurance 9,408 Urban policy 9,256 United States 9,207 Usage 9,137 Urban transportation 7,417 Unitarian churches 6,431 Ultra-Orthodox Jews 5,954 Uniforms 5,801 Urdu literature 5,779 Unitarianism 5,740 User interfaces (Computer systems) 5,696 Underground movements, War 5,628 Ulama 5,357 Ukrainians 5,167 Ukrainian language 5,131 Urdu poetry 5,095 Ukrainian literature 4,952 Ukraine 4,288 User Interfaces and Human Computer Interaction 3,966 Urban ecology (Sociology) 3,918 Utilization 3,852 Universalism 3,810 Upper class 3,626 Usury 3,552 Unitarian Universalist churches 3,265 Urban poor 3,185 Underground press publications 3,149 Union catalogs 3,118 Ukiyoe 3,078 Urban economics 3,023 Urdu language 2,786 Universities 2,686 Union lists 2,492 Underwater archaeology 2,386 United Nations 2,330 Unitarians 2,071 Uncles 2,044 Undocumented immigrants 2,035 Uranium 2,015 Underground literature 2,014 Urology 1,979 Uncertainty 1,955 Urban, Rural and Regional Development 1,919 Utopias in literature 1,860 Ukrainian poetry 1,837 Urinary organs 1,819 Universités 1,811 Uterus 1,785 Urbanisation 1,771 User charges 1,770 Urine 1,727 Unity 1,681 Unidentified flying objects 1,662 Uranium ores 1,603 Urdu fiction 1,600 Undercover operations 1,594 Urban beautification 1,548 Urbanisme 1,505 Urban 1,489 Utilitarianism 1,461 Ubiquitous computing 1,448 Ultrasonic imaging 1,421 Ukrainian 1,420 Urban geography 1,381 Ukraine Conflict, 2014- 1,327 Urban transportation policy 1,327 Unmarried mothers 1,323 Upper atmosphere 1,323 Unitarian Universalists 1,318 Urologic Diseases 1,316 Ultrasonography 1,315 Urban landscape architecture 1,295 Universalist churches 1,253 Unified operations (Military science) 1,233 Unmarried couples 1,208 University extension 1,201 Usury laws 1,150 Unemployment rate 1,141 Ultraviolet radiation 1,119 Uighur (Turkic people) 1,108 Urdu 1,083 UE/CE Etats membres 1,073 Underground Railroad 1,055 Uranium mines and mining 1,041 Urban runoff 1,041 Universalists 1,031 Urban ecology (Biology) 989 Undocumented Immigrants 986 Umbanda (Cult) 980 Urban health 950 Unternehmen 949 Urban youth 946