Columbia subject headings:
Harvard subject headings:
Consanguinity--Congresses.
Consanguinity--Germany--Congresses.
Families--Germany--History--Congresses.
Families--History--Congresses.
Genealogy--Congresses
Germany--Genealogy--Congresses.
Heredity--Congresses.
Heredity--Germany--Congresses.
Princeton subject headings:
Consanguinity--Congresses.
Consanguinity--Germany--Congresses.
Families--Germany--History--Congresses.
Families--History--Congresses.
Genealogy--Congresses.
Germany--Genealogy--Congresses.
Heredity--Congresses.
Heredity--Germany--Congresses.