Findings:
- Barbershop quartet
- piano quartet
- Kronos Quartet
- The Alexandria Quartet
- Helicopter String Quartet
- Four Quartets
- Fred Frith Guitar Quartet
- James Taylor Quartet
- Das literarische Quartett
- Beethoven string quartet
- Bartok string quartets
- Schoenberg String Quartet no.2
- Apparat Organ Quartet
- Beethoven's Late String Quartets
- The Abarat Quartet
- Beethoven String Quartet Op. 18, No. 1 in F Major
- Dave Brubeck Quartet
- The Dalemark Quartet
- Thelonious Monk Quartet with John Coltrane at Carnegie Hall
- String quartet tribute
- Sexual Disaster Quartet
- Quartet for virus, kitten, miso and crucifix
- Quartet for the End of Time
- Black barbershop
- barbershop
- After-Hours Odds at a Reputable Barbershop
- If you keep going into the barbershop you'll end up getting a haircut
- The Great Barbershop Race Wars
- John Coltrane Quartet
- Lanz quartet
- Modern Jazz Quartet
- Keith Jarrett's American Quartet
- Quartet
- Keith Jarrett's European Quartet
- The Million Dollar Quartet
- World Saxophone Quartet
- Charles Lloyd Quartet
- Hampton String Quartet
- string quartet
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