Columbia subject headings:
Architecture, Domestic--Europe, German-speaking--Designs and plans.
Architecture--Europe, German-speaking--History--20th century.
Housing, Single family--Europe, German-speaking--Designs and plans.
Harvard subject headings:
Architecture, Domestic--Europe--Designs and plans.
Architecture--Europe--History--20th century
Buildings--Additions--Europe.
Dwellings--Remodeling--Europe.
Housing, Single family--Europe--Designs and plans.
Princeton subject headings: