"Sie wird das nothwendigste und härteste und die hauptsache in der Musique niemahlen bekommen, nämlich das tempo, weil sie sich vom jugend auf völlig befliessen hat, nicht auf den tact zu spiellen."
Letter to Leopold Mozart (24 October 1777), from Mozart: The Man and the Artist, as Revealed in his own Words by Friedrich Kerst, trans. Henry Edward Krehbiel (1906) http://www.gutenberg.org/dirs/etext03/wamma11.txt
Wolfgang Amadeus Mozart: Frasi in inglese (pagina 2)
Wolfgang Amadeus Mozart era compositore, pianista, organista e violinista austriaco. Frasi in inglese.Letter to Leopold Mozart (4 April 1787), from The Mozart-Da Ponte Operas by Andrew Steptoe [Oxford University Press, 1988, ISBN 0-198-16221-9], p. 84.
in a letter to his father, 1782
Origine: Letter to his sister (Milan, 26 January 1770), from Contradictory Quotations, Longman Group Ltd., 1983. Rendered as "as the sows piss" in Letters of Wolfgang Amadeus Mozart, trans. Hans Mersmann, Dover Publications, 1972 (originally 1928)
From a letter now regarded as a forgery by Johann Friedrich Rochlitz http://www.aproposmozart.com/Stafford%20--%20Mozart%20and%20genius.rev.ref.pdf, http://www.mozartforum.com/Lore/article.php?id=108, http://www.mozartforum.com/Lore/article.php?id=106
Misattributed