Columbia subject headings:
Schopenhauer, Arthur, 1788-1860--Archives.
Stadt- und Universitätsbibliothek Frankfurt am Main--Catalogs.
Harvard subject headings:
Schopenhauer, Arthur, 1788-1860--Archives--Catalogs.
Schopenhauer, Arthur, 1788-1860--Friends and associates--Registers.
Princeton subject headings:
Schopenhauer, Arthur, 1788-1860--Archives--Catalogs.
Schopenhauer, Arthur, 1788-1860--Friends and associates--Registers.