b'Underground railroadsUltrasonics Underground architectureDewey: 534.5 Geographic Note: May subdivide geographicallyUse For: Inaudible sound; Supersonics Dewey: 624.1; 690; 720Broader Term(s): Sound Use For: Underground designNarrower Term(s):Ultrasonic waves Broader Term(s): ArchitectureUltraviolet rays Narrower Term(s):BasementsEarth sheltered housesDewey: 535.01; 621.36Use For: Rays, Ultra-violet Underground dance musicBroader Term(s): Electromagnetic waves Use: Electronic dance musicRadiation Underground designRelated Term(s): PhototherapyRadiotherapy Use: Underground architectureUmbrellas and parasols Underground economyDewey: 391.4; 685 Geographic Note: May subdivide geographicallyUse For: Parasols Dewey: 381Broader Term(s): Clothing and dress Scope Note: Use for materials on goods andservices that are produced and soldUN legally but not reported or taxed.Use: United Nations Materials on illegal trade aimed atUN (Political Party) avoiding government regulations,such as fixed prices or rationing, areUse: Union nationale entered under Black market.Unauthorized immigrants Use For: Economy, Underground; HiddenGeographic Note: May subdivide geographically economy; Informal sectorDewey: 323.6; 325; 342 (Economics); Parallel economy;Use For: Aliens, Illegal; Illegal aliens; Second economy; ShadowUndocumented aliens economy; Untaxed incomeBroader Term(s): Immigration and emigration Broader Term(s): EconomicsNoncitizens Small businessRelated Term(s): Sanctuary movement Narrower Term(s):BarterUnderground economy Related Term(s): Black marketUnauthorized immigrantsUnbeliefUse: Skepticism Underground filmsUse: Experimental filmsUnborn childUse: Fetus Underground housesUse: Earth sheltered housesUnclesGeographic Note: May subdivide geographically Underground literatureDewey: 306.87 Use: Alternative pressBroader Term(s): Family Underground movementsUnconventional warfare Use names of wars with the subdivision UndergroundUse: Guerrilla warfare movements, e.g. World War, 1939-1945 Underground movements [to be added as needed]Undenominational churchesUse: Community churches Underground pressUse: Alternative pressUnderachieversGeographic Note: May subdivide geographically Underground railroadDewey: 371.28 Geographic Note: May subdivide geographicallyBroader Term(s): Students Dewey: 326Related Term(s): SlaveryCanadaUnderdeveloped areas SlaveryUnited StatesUse: Developing countriesUnderground railroadsUndergraduates Use: SubwaysUse: College students987'