쇼팽 Contredanse in G-flat major, B. 17

The Contradanse in G flat major is a work apparently written by Frédéric Chopin in either 1827 or 1829. The authenticity of the piece is actually a subject of dispute among scholars, as the only surviving manuscript is not in Chopin's handwriting. The work lacks an opus number, so it is usually referred to by its Brown catalogue number, B. 17. It was published in 1934, contrary to his wish that all his unpublished manuscripts be burned.