Compositions by Mozart are given K numbers after which musicologist and composer who catalogued them?
Symphony, K. 74g (Mozart) numbered symphonies. The unnumbered symphonies (some, including K. 74g, published in supplements to the Alte-Mozart Ausgabe until 1910) are sometimes given numbers in the range 42 to 56, even though they were written earlier than Mozart's Symphony No. 41 (written in 1788). The symphony K. 74g is given the number 54 in this numbering scheme. This symphony (among others) was known to Ludwig Ritter von Köchel only by an incipit in the catalogue of Breitkopf & Härtel, and so he placed it in the Anhang of the Köchel catalogue as Anh. 216. A set of parts (now lost) was discovered
Haydn and Mozart and Vanhal, though little-remembered now, were well-known composers (particularly of symphonies) of the time. (Many, if not most, now believe that Dittersdorf actually played first violin, given his world-class technique, and Haydn second.) The composer Maximilian Stadler also remembered chamber music performances in which Haydn and Mozart participated: the two of them took the viola parts in performances of Mozart's string quintets, K. 515, 516, and 593. Haydn freely praised Mozart, without jealousy, to his friends. For instance, he wrote to Franz Rott, To the musicologist Charles Burney, he said, "I have often been flattered by my friends with having