Ludwig Ritter von Köchel since undergone revisions. Mozart's works are often referred to by their K-numbers ("cf." opus number); for example, the "Jupiter" symphony, "Symphony No. 41" K. 551. Moreover, Köchel arranged Mozart's works into twenty-four categories, which were used by Breitkopf & Härtel when they published the first complete edition of Mozart's works from 1877 to 1910, a venture partly funded by Köchel. He also catalogued the works of Johann Fux. Ludwig Ritter von Köchel Ludwig Alois Friedrich Ritter von Köchel (; 14 January 1800 – 3 June 1877) was an Austrian musicologist, writer, composer, botanist and publisher. He is best known for
Catalogues of Beethoven compositions catalogue in the 1950s, in which he included pieces not included in the 19th century complete edition published by Breitkopf and Härtel. Hess included many more fragmentary works than did Kinsky, and his catalog runs to 335 entries in the "Hauptkatalog" (main catalogue), and 66 "doubtful and falsely-attributed" works in an appendix. Many pieces have both WoO and H numbers. Beethoven's compositions are also organized through the Biamonti Catalogue, compiled by Giovanni Biamonti and published in 1968. This work is an attempt to chronologically order all of Beethoven's creative output, in a manner similar to the catalogue of Franz Schubert's