I earnestly request to send me the music which my gracious lord left behind him –– At the same I am sending the titles of two old works which would be suitable for the Archduke’s library. Although the auction the Birkenstock library and collection of paintings has not yet been held, Herr and Frau von Brentano (née Birkenstock) who live in the Erdbeergasse in the Landtrasse, would certainly let the Archduke have these works. In fact I mentioned this to the Archduke when he was here. Hence, if you consider it advisable, you yourself may now discuss the matter with the owners, for I do not know how old works of this kind should be sold –‘
Your most devoted servant
Beethoven