b'OpiatesOpen education Opera librettosUse: Open plan schools Dewey: 782.1026Open heart surgery Scope Note: Use for individual opera librettosand for collections of opera librettos.Use: HeartSurgery Use For: OperasLibrettosOpen housing Broader Term(s): LibrettosUse: Discrimination in housing Related Term(s): OperaStories, plots, etc.Open plan schools Opera plotsGeographic Note: May subdivide geographically Use: OperaStories, plots, etc.Dewey: 371.2 OperasScope Note: Use for materials on schools without Use: Operainterior walls.Use For: Interest centers approach to OperasLibrettosteaching; Learning center approach Use: Opera librettosto teaching; Open classroom Operating systems (Computers)approach to teaching; Openeducation Use: Computer operating systemsBroader Term(s): EducationExperimental Operation Desert Stormmethods Use: Persian Gulf War, 1991Related Term(s): Experimental schoolsIndividualized instruction Operational analysisOpen source software Use: Operations researchDewey: 005.3 Operational researchUse For: Open code software Use: Operations researchBroader Term(s): Computer softwareOperations researchOpen universities Geographic Note: May subdivide geographicallyUse: Free universities Dewey: 658.5Openings (Holes) Use For: Operational analysis; OperationalresearchUse: Holes Broader Term(s): ResearchOpera System theoryGeographic Note: May subdivide geographically Related Term(s): ManagementDewey: 782.1; 792.5 Systems engineeringScope Note: Use for musical scores and for Operations, Surgicalmaterials about the opera. Use: SurgeryUse For: Comic opera; Dramatic music;Operas OperettaBroader Term(s): Drama Geographic Note: May subdivide geographicallyMusical form Dewey: 782.1; 792.5Performing arts Scope Note: Use for musical scores and forVocal music materials on the operetta as aNarrower Term(s):Operetta musical form.OperaCanada Use For: Comic opera; Dramatic music;OperettasDewey: 782.1; 792.50971 Broader Term(s): Musical formOperaSound recordings OperaDewey: 782.1 Vocal musicBroader Term(s): Sound recordings Related Term(s): MusicalsOperaStories, plots, etc. OperettasDewey: 782.1026 Use: OperettaUse For: Opera plots OpiatesRelated Term(s): Opera librettos Use: Narcotics711'