Operas 421 World War, 1939-1945 308 Symphonies 288 Excerpts 278 Piano music 163 History 158 Instruction and study 156 more ... Ballets 153 Orchestral music 142 Sonatas (Piano) 124 Concertos (Piano) 120 Interpretation (Phrasing, dynamics, etc.) 112 Production and direction 103 Criticism and interpretation 89 Teaching 89 Aids and devices 87 instructional materials 87 Music 86 Music rehearsals 82 Opera 78 Overtures 77 Performance 77 Concertos (Violin) 72 Conductors (Music) 56 African Americans 49 Choreographers 49 Composers 47 Pianists 46 Suites (Orchestra) 43 Sonatas (Violin and piano) 42 less ...