Columbia subject headings:
Harvard subject headings:
Autographs--History--Congresses.
Manuscripts--History--Congresses.
Paleography--History--Congresses.
Signatures (Writing)--History--Congresses.
Princeton subject headings:
Autographs--Congresses.
Manuscripts--Congresses.
Paleography--Congresses.
Signatures (Writing)--Congresses.