Columbia subject headings:
France--Foreign relations--1852-1870--Congresses.
France--Foreign relations--Germany--Congresses.
Germany--Foreign relations--1848-1870--Congresses.
Germany--Foreign relations--France--Congresses.
Harvard subject headings:
France--Foreign relations--1852-1870--Congresses.
France--Foreign relations--Germany--Congresses.
Germany--Foreign relations--1848-1870--Congresses.
Germany--Foreign relations--France--Congresses.
Princeton subject headings:
France--Foreign relations--Germany--Congresses.
France--Relations--Germany--Congresses.
Germany--Foreign relations--France--Congresses.
Germany--Relations--France--Congresses.