Treasury of delightful solo vocal quartets:
Liebeslieder, Op. 52, 18 songs for vocal quartet (soprano, alto, tenor and bass) and piano four hands
Neue Liebeslieder, Op. 65, 14 songs and a closing piece for the same ensemble
Zigeunerlieder, Op. 103, 11 songs for vocal quartet and piano (one player).
Breitkopf & Härtel edition.