20. The Archduke owned as well a portfolio of ten cadenzas, now at the Gesellschaft der Musikfreunde in Vienna, said to be for concertos by Joseph Haydn. Anthony van Hoboken, Joseph Haydn: Thematisch-bibliographisches Werkverzeichnis, I (Mainz: B. Schott’s Söhne, 1957), 814, rules out the possibility that the cadenzas were composed by Haydn. The incipits are shown in Joseph Haydn: Werke, series 15, vol. II: Konzerte für Klavier (Cembalo) und Orchester, ed. Horst Walter and Bettina Wackernagel (Munich: G. Henle, 1983), 200; see further xii, n. 49. I am grateful to James Webster for bringing this latter to my attention.