J. van Beethoven (1801 Vienne.) - NYPL Digital Collections

William Kinderman - The String Quartets of Beethoven-University of

PDF) Beethoven's Tempo Indications

Trombone History: 19th Century (1801-1825) - Will Kimball

The young Ludwig van Beethoven 1770-1827 1806 by Isidor Neugass

Bibliography, PDF

Karl van Beethoven, 1801-1858. L. v. B.'s Nephew - NYPL Digital

L'arc de cercle, or the Movement of Modernism (1620–2020

J. van Beethoven (1801 Vienne.) - NYPL Digital Collections

J. van Beethoven (1801 Vienne.) - NYPL Digital Collections

Beethoven in his Study - NYPL Digital Collections