Columbia subject headings:
French language--History--Congresses.
Harvard subject headings:
French language--History--Congresses.
French language--Spoken French--History--Congresses.
French language--Written French--History--Congresses.
Princeton subject headings:
French language--History--Congresses.
French language--Spoken French--History--Congresses.
French language--Written French--History--Congresses.