Columbia subject headings:
Beethoven, Ludwig van, 1770-1827. Quartets,
Composers--Germany--Biography.
Composers--Germany--Correspondence.
Harvard subject headings:
Beethoven, Ludwig van, 1770-1827. Quartets,
Composers--Germany--Biography
Composers--Germany--Correspondence
Princeton subject headings:
Beethoven, Karl van, 1806-1858.
Beethoven, Ludwig van, 1770-1827--Family.
Beethoven, Ludwig van, 1770-1827. Quartets, no. 15, op. 132,