Columbia subject headings:
Harvard subject headings:
Authors, German--Books and reading--History--Congresses.
Authorship--History--Congresses.
Libraries--Germany--History--Congresses.
Libraries--Germany--Special collections--History--Congresses.
Private libraries--Germany--History--Congresses.
Princeton subject headings:
Authors, German--Books and reading--Congresses.
Authorship--Congresses.
Libraries--Germany--History--Congresses.
Private libraries--Germany--History--Congresses.