Columbia subject headings:
Architecture, Domestic--Germany--Kalkar (Düsseldorf)
Kalkar (Düsseldorf, Germany)--History.
Ulftsche Haus (Kalkar, Düsseldorf, Germany)
Harvard subject headings:
Architecture, Gothic--Germany--Cologne.
Architecture, Medieval--Germany--Cologne.
Cologne (Germany)--Buildings, structures, etc.
Kalkar (Cologne, Germany)
Stone houses--Germany--Cologne.
Princeton subject headings:
Architecture, Domestic--Germany--Kalkar (Düsseldorf).
Hellendorn, Alard Gerhard, 1684-1760.
Kalkar (Düsseldorf, Germany)--Buildings, structures, etc.
Kalkar (Düsseldorf, Germany)--History.
Ulftsche Haus (Kalkar, Düsseldorf, Germany).