Autograph letter signed from Beethoven to Countess Marie Erdödy about the “Archduke” Trio, Opus 97, no place or date [Vienna, March 1815] 2 p., octavo (20.8 x 12.9 cm), integral blank, autograph address panel, red wax seal with Beethoven’s monogram (”LVB”), small seal tear, traces of mount, creasing, a few tiny stains