Köchel catalogue son's earlier works; Mozart's catalogue of his own compositions (begun in February 1784 with K. 449) allows relatively precise dating of many of his later works. The catalogue included the opening bars of each piece, known as an incipit. Köchel divided the corpus into a main chronology of 626 works, and five appendices ("" in German, abbreviated to "Anh.") The appendices (Anh. I-V) included: Since Köchel published his original catalogue in 1863 (now referred to as K), the dating of Mozart's compositions has been subject to constant revision. Many more pieces have since been found, re-dated, re-attributed and re-numbered, requiring
Dr K–Sextett Dr K–Sextett The Dr K–Sextett is a short, occasional composition for six instrumentalists, written in 1969 by Karlheinz Stockhausen and given the number 28 in his catalogue of works. The Sextet was composed as the result of a request made to eleven composers in January 1969 by the London office of Universal Edition for short pieces of music to celebrate the 80th birthday of Dr. Alfred Kalmus, who had been Universal's London director since 1936. All of the pieces were scored for performance by members of the Pierrot Players . Collectively titled "A Garland for Dr. K.", the eleven works