Columbia subject headings:
German letters--History and criticism--Congresses.
Letter writing, German--History--19th century--Congresses.
Harvard subject headings:
German letters--History and criticism--Congresses.
Letter writing, German--History--19th century--Congresses.
Princeton subject headings:
German letters--History and criticism--Congresses.
Letter writing, German--History--19th century--Congresses.