Columbia subject headings:
Germany--History--To 1517--Databases.
Germany--History--To 1517--Sources--Databases.
Middle Ages--Databases.
Middle Ages--Sources--Databases.
Harvard subject headings:
Princeton subject headings:
Databases.
Germany--History--To 1517--Databases.
Germany--History--To 1517--Sources--Databases.
Middle Ages--Databases.
Middle Ages--Sources--Databases.