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
Schubert Thematic Catalogue Schubert Thematic Catalogue Schubert: Thematic Catalogue of all his Works in Chronological Order, also known as the Deutsch catalogue, is a numbered list of all compositions by Franz Schubert compiled by Otto Erich Deutsch. Since its first publication in 1951, Deutsch (abbreviated as D or D.) numbers are used for the unique identification of Schubert's compositions. The Deutsch catalogue was first published in London in 1951, as "Schubert: Thematic Catalogue of all his Works in Chronological Order, compiled by O. E. Deutsch, in collaboration with Donald R. Wakeling." In 1978, as part VIII Supplement / Volume 4 of the New