In what century was the the style of voices popular that the Liebeslieder Walzer, Op. 52 was in?
Ländler The Ländler (] ) is a folk dance in  time which was popular in Austria, south Germany, German Switzerland, and Slovenia at the end of the 18th century.
Piano ballad In 19th century romantic music, a piano ballad is a piece for solo piano written in a balletic narrative style, often with lyrical elements interspersed. This type of work made its first appearance with Chopin's Ballade No. 1 in G minor, op. 23 of 1836, closely followed by the ballad included in Clara Schumann's "Soirées musicales" Op.6 published in the same year.