Columbia subject headings:
Harvard subject headings:
Alsace (France)--History--Sources.
Germany--History--Hohenstaufen, 1138-1254--Sources.
Strasbourg (France)--History--Sources.
Princeton subject headings:
Alsace (France)--History--Sources.
Germany--History--Hohenstaufen, 1138-1254--Sources.
Strasbourg (France)--History--Sources.